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  • Additional options in MDL

    - by Jane Zhang
        The Metadata Loader(MDL) enables you to populate a new repository as well as transfer, update, or restore a backup of existing repository metadata. It consists of two utilities: metadata export and metadata import. The export utility extracts metadata objects from a repository and writes the information into a file. The import utility reads the metadata information from an exported file and inserts the metadata objects into a repository.      While the Design Client provides an intuitive UI that helps you perform the most commonly used export and import tasks, OMBPlus scripting enables you to specify some additional options, and manage a control file that allows you to perform more specialized export and import tasks. Is it possible to utilize these options in MDL from Design Client? This article will tell you how to achieve it.      A property file named mdl.properties is used to configure the additional options. It stores options in name/value pairs. This file can be created and placed under the directory <owb installation path>/owb/bin/admin/. Below we will introduce the options that can be specified in the mdl.properties file. 1. DEFAULTDIRECTORY     When we open a Metadata Export/Import dialog in Design Client, a default directory is provided for MDL file and log file. For MDL Export, the default directory is <owb installation path>/owb/bin/. As for MDL Import, the default directory is <owb installation path>/owb/mdl/. It may not be the one you would want to use as a default. You can specify the option DEFAULTDIRECTORY in the mdl.properties file to set your own default directory for MDL Export/Import, for example, DEFAULTDIRECOTRY=/tmp/     In this example, the default directory is set to /tmp/. Be sure the value ends with a file separator since it represents a directory. In Windows, the file separator is “\”. In linux, the file separator is “/”. 2. MDLTRACEFILE     Sometimes we would like to trace the whole process of MDL Export/Import, and get detailed information about operations to help developers or supports troubleshooting. To turn on MDL trace, set the option MDLTRACEFILE in the mdl.properties file. MDLTRACEFILE=/tmp/mdl.trc    The right side of the equals sign is to specify the name of the file for MDL trace information to be written. If no path is specified, the file will be placed under directory <owb installation path>/owb/bin/admin/. However, the trace file may be large if the MDL file contains a large number of metadata objects, so please use this option sparingly. 3. CONTROLFILE       We can use a control file to specify how objects are imported or exported. We can set an option called CONTROLFILE in the mdl.properties file, so the control file can also be utilized in Design Client, for example, CONTROLFILE=/tmp/mdl_control_file.ctl     The control file stores options in name/value pairs. When using control file, be sure the file exists, otherwise an exception java.lang.Exception: CNV0002-0031(ERROR): Cannot find specified file will be thrown out during MDL Export/Import.      Next we will introduce some options specified in control file. ZIPFILEFORMAT     By default, MDL exports objects into a zip format file. This zip file has an .mdl extension and contains two files. For example, you export the repository metadata into a file called projects.mdl. When you unzip this MDL file, you obtain two files. The file projects.mdx contains the repository objects. The file mdlcatalog.xml contains internal information about the MDL XML file. Another choice is to combine these two files into one unzip text format file when doing MDL exporting.    In OMBPlus command related to MDL, there is an option called FILE_FORMAT which is used to specify the file format for the exported file. Its acceptable values are ZIP or TEXT. When the value TEXT is selected, the exported file is in text format, for example, OMBEXPORT MDL_FILE '/tmp/options_file_format_test.mdl' FILE_FORMAT TEXT FROM PROJECT 'MY_PROJECT'    How to achieve this via Design Client when doing an MDL exporting? Here we have another option called ZIPFILEFORMAT which has the same function as the FILE_FORMAT. The difference is the acceptable values for ZIPFILEFORMAT are Y or N. When the value is set to N, the exported file is in text format, otherwise it is in zip file format. LOGMESSAGELEVEL     Whenever you export or import repository metadata, MDL writes diagnostic and statistical information to a log file. Their are 3 types of status messages: Informational, Warning and Error. By default, the log file includes all types of message. Sometimes, user may only care about one type of messages, for example, they would like only error messages written to the log file. In order to achieve this, we can set an option called LOGMESSAGELEVEL in control file. The acceptable values for LOGMESSAGELEVEL are ALL, WARNING and ERROR. ALL: If the option LOGMESSAGELEVEL is set to ALL, all types of messages (Informational, Warning and Error) will be written into the log file. WARNING: If the option LOGMESSAGELEVEL is set to WARNING, only warning messages will be written into log file. ERROR: If the option LOGMESSAGELEVEL is set to ERROR, only error messages will be written into log file. UPDATEPROJECTATTRIBUTES, UPDATEMODULEATTRIBUTES      These two options are used to decide whether updating the attributes of projects/modules. The options work when projects/modules being imported already exist in repository and we use update metadata mode or replace metadata mode to do the MDL import. The acceptable values for these two options are Y or N. If the value is set to Y, the attributes of projects/modules will be updated, otherwise not.      Next, let’s give an example to see how these options take effect in MDL. 1. First of all, create the property file mdl.properties under the directory <owb installation path>/owb/bin/admin/. 2. Specify the options in the mdl.properties file, see the following screenshot. 3. Create the control file mdl_control_file.ctl under the directory /tmp/. Set the following options in control file. 4. Log into the OWB Design Client. 5. Create an Oracle module named ORA_MOD_1 under the project MY_PROJECT, then export the project MY_PROJECT into file my_project.mdl. 6. Check the trace file mdl.trc under the directory /tmp/. In this file, we can see very detail information for the above export task. 7. Check the exported MDL file. The file my_project.mdl is in text format. Opening the file, you can see the content of the file directly. It concats the file my_project.mdx and mdlcatalog.xml. 8. Modify the project MY_PROJECT and Oracle module ORA_MOD_1, add descriptions for them separately. Delete the location created in step 5. 9. Import the MDL file my_project.mdl. From the Metadata Import dialog, we can see the default directory for MDL file and log file has been changed to /tmp/. Here we use update metadata mode, match by names to do the importing. 10. After importing, check the description of the project MY_PROJECT, we can see the description is still there. But the description of the Oracle module ORA_MOD_1 has gone. That because we set the option UPDATEPROJECTATTRIBUTES to N, and set the option UPDATEMODULEATTRIBUTES to Y. 11. Check the log file, the log file only contains warning messages and the log message level is set to WARNING.      For more details about the 3 types of status messages, see Oracle® Warehouse Builder Installation and Administration Guide11g Release 2.

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  • Windows Azure Evolution &ndash; Preview Developer Portal

    - by Shaun
    With the MEET Windows Azure event on 7th June, there are many new features and updates in windows azure platform. In the coming several posts I will try to cover some of them. And in the first post here I would like to just have a quick walkthrough of the new preview developer portal.   History of the Developer Portal If you have been working with windows azure since 2009 or 2010, you should remember the first version of the developer portal. It was built in HTML with very limited features. I have the impression when I was using is old one. The layout is not that attractive and you have very limited features. On November, 2010 alone with the SDK 1.3 release, the developer portal was getting a big jump. In order to give more usability and features this it turned to be built on Silverlight. Hence it runs like a desktop application with many windows, lists, commands and context menus. From 2010 till now many features were involved into this portal, such as the remote desktop, co-admin, virtual connect, VM role, etc.. And the portal itself became more and more complicated. But it brought some problems by using the Silverlight. The first one is the browser capability. As you know in most mobile and tablet device the browser doesn’t allow the rich content plugin, such as Flash and Silverlight. This means people cannot open and configure their azure services from their iPad, iPhone and Windows Phone, etc., even though what they need may just be restart a hosted service, or view the status of their databases. Another problem is the performance. Silverlight provides rich experience to the users, but also needs more bandwidth. So in this upgrade the preview developer portal will be back to use HTML, with JavaScript, as a mobile friendly, cross browser, interactively web site.   Preview Portal vs. Silverlight Portal Before I started to talk about the new preview portal I’d better highlight that, this preview portal is a PREVIEW version, which means even though you can do almost all features that already in the old one, as long as some cool new features I will mention in the coming several posts, there are something still under developed and migrated. So sometimes you need to switch back to the old one. For example, in preview portal there is no co-admin manage function, no remote desktop function and the SQL database manage function will take you back to the old SQL Azure Manage Portal. But as Microsoft said these missing features will be moved in the preview portal in the couple of next few months. Since the public URL of the developer portal, https://windows.azure.com/, had been changed to point to this preview one, you need to click to preview button on top of the page and click the “Take me to the previous portal” link.   Overview There are four parts in the preview portal. On the top is the header which shows the account you are currently logging in. If you click on the header it will show the top menu of windows azure, where you can navigate to the windows azure home page, the price information page, community and account, etc.. The navigation bar is on the left hand side, with the categories listed below. ALL ITEMS All items in your windows azure account, includes the web sites, services, databases, etc.. WEB SITES The web sites in your windows azure account. It will only show the web sites you have. The linked resources will be shown if you drill down into a web site. VIRTUAL MACHINES The virtual machines that you had been deployed to azure. CLOUD SERVICES All windows azure hosted services in your account. SQL DATABASES All SQL databases (SQL Azure) in your account. STORAGE All windows azure storage services in your account. NETWORKS The virtual network (Windows Azure Connect) you had been created. The available items will be listed in the main part of the page based on which category your currently selected. If there’s no item it will show the link to you to quick create. At the bottom of the page there will be the command and information bar. Based on what is selected and what is performed by the user, it will show the related information and commands. For example, in the image below when I was creating a new web site, the information bar told me that my web site is being provisioned; and there are two commands in the command bar. And once it ready the command bar will show some commands that I can do to my new web site. The “Web Sites” is a new feature introduced alone with this upgrade. It gives us an easier and quicker way to establish a website from the scratch or from some existing library. I will introduce it more details in the coming next post. Also in the command bar you can create a service by clicking the NEW button. It will slide the creation panel up to you.   Where’s My Hosted Services The Windows Azure Hosted Services had been renamed to the Cloud Services. Create a new service would be very easy. Just click the NEW button at the bottom of the page, and select the CLOUD SERVICE and QIUICK CREATE. This will create a blank hosted service without deployment and certificate. It just needs you to specify the service URL and the affinity/region. Then the service will be shown in the list. If you clicked the item all information will be shown in the main part. Since there’s no package deployed to this service so currently we cannot see any information about it. But we can upload the package by using the command at the bottom. And as you can see, we could manage the configuration, instances, certificates and we can scale up and down (change the VM size), in and out (increase and decrease the instance count) to our service. Assuming I had created an ASP.NET MVC 3 web role project in Visual Studio and completed the package. Then I can click the UPLOAD button in this page to deploy my package. In the popping up window I just specify my deployment name, package file and configure file. Also I can check the box below so that it will NOT warn me if only one instance of this deployment. Once we clicked the OK button our package will be uploaded and provisioned by the platform. After a while we can see the service was ready from the information bar. We can have the basic information about this service and deployment if we to the dashboard page. For example the usage overview diagram, status, URL, public IP address, etc.. In the configure page we can view and change the CSCFG content such as the monitor setting, connection strings, OS family. In scale page we can increase and decrease the count of the instances. And in the instances page we can view all instances status. And, if your services is using some SQL databases and storages they will be shown as the linked resources under the linked resources page. And you can manage the certificates of this service as well under the certificates page.   How About My Storage Services The storage service can be managed by clicking into the STORAGES link in the navigation bar. And we can create a new storage service from the NEW button. After specify the storage name and region it will be previsioned by the platform. If you want to copy or manage the storage key you can just click the Manage Keys button at the bottom, which is very easy. What I want to highlight here is that, you can monitor your storage service by enabling the monitor configuration. Click the storage item in the list and navigate to the configure page. As you can see in the page you can enable the monitoring for blob, table and queue. And you can also enable the logging when any requests come to the storage. But as the tooltip shown in the page, enabling the monitoring and logging will increase the usage of the storage, which means increase the bill of them. So make sure you enable them properly.   And My SQL Databases (SQL Azure) The last thing I want to quick introduce is the SQL databases, which was formally named SQL Azure. You can create a new SQL Database Server and a new database by clicking the ADD button under the SQL Database navigation item. In the popping up windows just specify the database name, the edition, size, collation and the server. You can select an existing SQL Database Server if you have, or cerate a new one. If you selected to create a new server, there will be another step you need to do, which is specify the server login, password and the region. Once it ready you can mange your databases as well as the servers in the portal. In a particular server you can update the firewall settings in its Configure page. So, What Else There are some other area on the preview portal I didn’t cover, such as the virtual machines, virtual network and web sites. Regarding the virtual machines and web sites I will talk about them in the future separated post. Regarding the virtual network, it the Windows Azure Connect we are familiar with. But as I mention in the beginning of this post, the preview portal is still under developed. Some features are not available here. For example, you cannot manage the co-admin of your subscriptions, you cannot open the remote desktop on your hosted services, and you cannot navigate to the Windows Azure Service Bus, Access Control and Caching, which formally named Windows Azure AppFabric directly. In these cases you need to navigate back to the old portal. So in the coming several months we might need to use both these two sites.   Summary In this post I quick introduced the new windows azure developer portal. Since it had been rearranged and renamed I demonstrated some features that existing in the old portal, such as how to create and deploy a hosted service, how to provision a storage service and SQL database. All features in the old portal had been, is being and will be migrated into this new portal, but some of them were in a different category and page we need to figure out.   Hope this helps, Shaun All documents and related graphics, codes are provided "AS IS" without warranty of any kind. Copyright © Shaun Ziyan Xu. This work is licensed under the Creative Commons License.

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  • Udev webcam rule read, but not respected?

    - by user89305
    I have two usb-webcams on them machine, but at bot they some switch /dev/video number. The solution to this problem seems to be new udev rule. I have added this rule in/etc/udev/rules.d/jj-video.rules: Fix webcam 1 KERNEL=="video1", SUBSYSTEM=="video4linux", SUBSYSTEMS=="usb", ATTRS{idVendor}=="1d6b", ATTRS{idProduct}=="0001", SYMLINK+="webcam1" Fix webcam 2 KERNEL=="video2", SUBSYSTEM=="video4linux", ATTR{name}=="Logitech QuickCam Pro 3000", KERNELS=="0000:00:1d.0", SUBSYSTEMS=="pci", DRIVERS=="uhci_hcd", ATTRS{vendor}=="0x8086", ATTRS##{device}=="0x2658", SYMLINK+="webcam2" but the symlinks are not created. I have tried many different combinations in this file. The present ones are just my lates attempts. I found the parameters in: jjk@eee-old:~$ udevadm info -a -p $(udevadm info -q path -p /class/video4linux/video1) Udevadm info starts with the device specified by the devpath and then walks up the chain of parent devices. It prints for every device found, all possible attributes in the udev rules key format. A rule to match, can be composed by the attributes of the device and the attributes from one single parent device. looking at device '/devices/pci0000:00/0000:00:1d.0/usb2/2-2/2-2:1.0/video4linux/video1': KERNEL=="video1" SUBSYSTEM=="video4linux" DRIVER=="" ATTR{name}=="Logitech QuickCam Pro 3000" ATTR{index}=="0" ATTR{button}=="0" looking at parent device '/devices/pci0000:00/0000:00:1d.0/usb2/2-2/2-2:1.0': KERNELS=="2-2:1.0" SUBSYSTEMS=="usb" DRIVERS=="Philips webcam" ATTRS{bInterfaceNumber}=="00" ATTRS{bAlternateSetting}==" 9" ATTRS{bNumEndpoints}=="02" ATTRS{bInterfaceClass}=="0a" ATTRS{bInterfaceSubClass}=="ff" ATTRS{bInterfaceProtocol}=="00" ATTRS{supports_autosuspend}=="0" looking at parent device '/devices/pci0000:00/0000:00:1d.0/usb2/2-2': KERNELS=="2-2" SUBSYSTEMS=="usb" DRIVERS=="usb" ATTRS{configuration}=="" ATTRS{bNumInterfaces}==" 3" ATTRS{bConfigurationValue}=="1" ATTRS{bmAttributes}=="a0" ATTRS{bMaxPower}=="500mA" ATTRS{urbnum}=="371076" ATTRS{idVendor}=="046d" ATTRS{idProduct}=="08b0" ATTRS{bcdDevice}=="0002" ATTRS{bDeviceClass}=="00" ATTRS{bDeviceSubClass}=="00" ATTRS{bDeviceProtocol}=="00" ATTRS{bNumConfigurations}=="1" ATTRS{bMaxPacketSize0}=="8" ATTRS{speed}=="12" ATTRS{busnum}=="2" ATTRS{devnum}=="2" ATTRS{devpath}=="2" ATTRS{version}==" 1.10" ATTRS{maxchild}=="0" ATTRS{quirks}=="0x0" ATTRS{avoid_reset_quirk}=="0" ATTRS{authorized}=="1" ATTRS{serial}=="01402100A5000000" looking at parent device '/devices/pci0000:00/0000:00:1d.0/usb2': KERNELS=="usb2" SUBSYSTEMS=="usb" DRIVERS=="usb" ATTRS{configuration}=="" ATTRS{bNumInterfaces}==" 1" ATTRS{bConfigurationValue}=="1" ATTRS{bmAttributes}=="e0" ATTRS{bMaxPower}==" 0mA" ATTRS{urbnum}=="34" ATTRS{idVendor}=="1d6b" ATTRS{idProduct}=="0001" ATTRS{bcdDevice}=="0302" ATTRS{bDeviceClass}=="09" ATTRS{bDeviceSubClass}=="00" ATTRS{bDeviceProtocol}=="00" ATTRS{bNumConfigurations}=="1" ATTRS{bMaxPacketSize0}=="64" ATTRS{speed}=="12" ATTRS{busnum}=="2" ATTRS{devnum}=="1" ATTRS{devpath}=="0" ATTRS{version}==" 1.10" ATTRS{maxchild}=="2" ATTRS{quirks}=="0x0" ATTRS{avoid_reset_quirk}=="0" ATTRS{authorized}=="1" ATTRS{manufacturer}=="Linux 3.2.0-29-generic uhci_hcd" ATTRS{product}=="UHCI Host Controller" ATTRS{serial}=="0000:00:1d.0" ATTRS{authorized_default}=="1" looking at parent device '/devices/pci0000:00/0000:00:1d.0': KERNELS=="0000:00:1d.0" SUBSYSTEMS=="pci" DRIVERS=="uhci_hcd" ATTRS{vendor}=="0x8086" ATTRS{device}=="0x2658" ATTRS{subsystem_vendor}=="0x1043" ATTRS{subsystem_device}=="0x82d8" ATTRS{class}=="0x0c0300" ATTRS{irq}=="23" ATTRS{local_cpus}=="ff" ATTRS{local_cpulist}=="0-7" ATTRS{dma_mask_bits}=="32" ATTRS{consistent_dma_mask_bits}=="32" ATTRS{broken_parity_status}=="0" ATTRS{msi_bus}=="" looking at parent device '/devices/pci0000:00': KERNELS=="pci0000:00" SUBSYSTEMS=="" DRIVERS=="" jjk@eee-old:~$ And tested the setup: sudo udevadm --debug test /sys/class/video4linux/video1 main: runtime dir '/run/udev' run_command: calling: test adm_test: version 175 This program is for debugging only, it does not run any program, specified by a RUN key. It may show incorrect results, because some values may be different, or not available at a simulation run. parse_file: reading '/lib/udev/rules.d/40-crda.rules' as rules file parse_file: reading '/lib/udev/rules.d/40-fuse.rules' as rules file parse_file: reading '/lib/udev/rules.d/40-gnupg.rules' as rules file parse_file: reading '/lib/udev/rules.d/40-hplip.rules' as rules file parse_file: reading '/lib/udev/rules.d/40-ia64.rules' as rules file parse_file: reading '/lib/udev/rules.d/40-inputattach.rules' as rules file parse_file: reading '/lib/udev/rules.d/40-libgphoto2-2.rules' as rules file parse_file: reading '/lib/udev/rules.d/40-libsane.rules' as rules file parse_file: reading '/lib/udev/rules.d/40-ppc.rules' as rules file parse_file: reading '/lib/udev/rules.d/40-usb_modeswitch.rules' as rules file parse_file: reading '/lib/udev/rules.d/40-xserver-xorg-video-intel.rules' as rules file parse_file: reading '/lib/udev/rules.d/42-qemu-usb.rules' as rules file parse_file: reading '/lib/udev/rules.d/50-firmware.rules' as rules file parse_file: reading '/lib/udev/rules.d/50-udev-default.rules' as rules file parse_file: reading '/lib/udev/rules.d/55-dm.rules' as rules file parse_file: reading '/lib/udev/rules.d/56-hpmud_support.rules' as rules file parse_file: reading '/lib/udev/rules.d/60-cdrom_id.rules' as rules file parse_file: reading '/lib/udev/rules.d/60-pcmcia.rules' as rules file parse_file: reading '/lib/udev/rules.d/60-persistent-alsa.rules' as rules file parse_file: reading '/lib/udev/rules.d/60-persistent-input.rules' as rules file parse_file: reading '/lib/udev/rules.d/60-persistent-serial.rules' as rules file parse_file: reading '/lib/udev/rules.d/60-persistent-storage-dm.rules' as rules file parse_file: reading '/lib/udev/rules.d/60-persistent-storage-tape.rules' as rules file parse_file: reading '/lib/udev/rules.d/60-persistent-storage.rules' as rules file parse_file: reading '/lib/udev/rules.d/60-persistent-v4l.rules' as rules file parse_file: reading '/lib/udev/rules.d/61-accelerometer.rules' as rules file parse_file: reading '/lib/udev/rules.d/64-xorg-xkb.rules' as rules file parse_file: reading '/lib/udev/rules.d/66-xorg-synaptics-quirks.rules' as rules file parse_file: reading '/lib/udev/rules.d/69-cd-sensors.rules' as rules file add_rule: IMPORT found builtin 'usb_id', replacing /lib/udev/rules.d/69-cd-sensors.rules:76 parse_file: reading '/lib/udev/rules.d/69-libmtp.rules' as rules file parse_file: reading '/lib/udev/rules.d/69-xorg-vmmouse.rules' as rules file parse_file: reading '/lib/udev/rules.d/69-xserver-xorg-input-wacom.rules' as rules file parse_file: reading '/etc/udev/rules.d/70-persistent-cd.rules' as rules file parse_file: reading '/etc/udev/rules.d/70-persistent-net.rules' as rules file parse_file: reading '/lib/udev/rules.d/70-printers.rules' as rules file parse_file: reading '/lib/udev/rules.d/70-udev-acl.rules' as rules file parse_file: reading '/lib/udev/rules.d/75-cd-aliases-generator.rules' as rules file parse_file: reading '/lib/udev/rules.d/75-net-description.rules' as rules file parse_file: reading '/lib/udev/rules.d/75-persistent-net-generator.rules' as rules file parse_file: reading '/lib/udev/rules.d/75-probe_mtd.rules' as rules file parse_file: reading '/lib/udev/rules.d/75-tty-description.rules' as rules file parse_file: reading '/lib/udev/rules.d/77-mm-ericsson-mbm.rules' as rules file parse_file: reading '/lib/udev/rules.d/77-mm-longcheer-port-types.rules' as rules file parse_file: reading '/lib/udev/rules.d/77-mm-nokia-port-types.rules' as rules file parse_file: reading '/lib/udev/rules.d/77-mm-pcmcia-device-blacklist.rules' as rules file parse_file: reading '/lib/udev/rules.d/77-mm-platform-serial-whitelist.rules' as rules file parse_file: reading '/lib/udev/rules.d/77-mm-qdl-device-blacklist.rules' as rules file parse_file: reading '/lib/udev/rules.d/77-mm-simtech-port-types.rules' as rules file parse_file: reading '/lib/udev/rules.d/77-mm-usb-device-blacklist.rules' as rules file parse_file: reading '/lib/udev/rules.d/77-mm-x22x-port-types.rules' as rules file parse_file: reading '/lib/udev/rules.d/77-mm-zte-port-types.rules' as rules file parse_file: reading '/lib/udev/rules.d/77-nm-olpc-mesh.rules' as rules file parse_file: reading '/lib/udev/rules.d/78-graphics-card.rules' as rules file parse_file: reading '/lib/udev/rules.d/78-sound-card.rules' as rules file parse_file: reading '/lib/udev/rules.d/80-drivers.rules' as rules file parse_file: reading '/lib/udev/rules.d/80-mm-candidate.rules' as rules file parse_file: reading '/lib/udev/rules.d/80-udisks.rules' as rules file parse_file: reading '/lib/udev/rules.d/85-brltty.rules' as rules file parse_file: reading '/lib/udev/rules.d/85-hdparm.rules' as rules file parse_file: reading '/lib/udev/rules.d/85-hplj10xx.rules' as rules file parse_file: reading '/lib/udev/rules.d/85-keyboard-configuration.rules' as rules file parse_file: reading '/lib/udev/rules.d/85-regulatory.rules' as rules file parse_file: reading '/lib/udev/rules.d/85-usbmuxd.rules' as rules file parse_file: reading '/lib/udev/rules.d/90-alsa-restore.rules' as rules file parse_file: reading '/lib/udev/rules.d/90-alsa-ucm.rules' as rules file parse_file: reading '/lib/udev/rules.d/90-libgpod.rules' as rules file parse_file: reading '/lib/udev/rules.d/90-pulseaudio.rules' as rules file parse_file: reading '/lib/udev/rules.d/95-cd-devices.rules' as rules file parse_file: reading '/lib/udev/rules.d/95-keyboard-force-release.rules' as rules file parse_file: reading '/lib/udev/rules.d/95-keymap.rules' as rules file parse_file: reading '/lib/udev/rules.d/95-udev-late.rules' as rules file parse_file: reading '/lib/udev/rules.d/95-upower-battery-recall-dell.rules' as rules file parse_file: reading '/lib/udev/rules.d/95-upower-battery-recall-fujitsu.rules' as rules file parse_file: reading '/lib/udev/rules.d/95-upower-battery-recall-gateway.rules' as rules file parse_file: reading '/lib/udev/rules.d/95-upower-battery-recall-ibm.rules' as rules file parse_file: reading '/lib/udev/rules.d/95-upower-battery-recall-lenovo.rules' as rules file parse_file: reading '/lib/udev/rules.d/95-upower-battery-recall-toshiba.rules' as rules file parse_file: reading '/lib/udev/rules.d/95-upower-csr.rules' as rules file parse_file: reading '/lib/udev/rules.d/95-upower-hid.rules' as rules file parse_file: reading '/lib/udev/rules.d/95-upower-wup.rules' as rules file parse_file: reading '/lib/udev/rules.d/97-bluetooth-hid2hci.rules' as rules file parse_file: reading '/etc/udev/rules.d/jj-video.rules' as rules file udev_rules_new: rules use 259284 bytes tokens (21607 * 12 bytes), 37913 bytes buffer udev_rules_new: temporary index used 67520 bytes (3376 * 20 bytes) udev_device_new_from_syspath: device 0x215103e0 has devpath '/devices/pci0000:00/0000:00:1d.0/usb2/2-2/2-2:1.0/video4linux/video1' udev_device_new_from_syspath: device 0x21510758 has devpath '/devices/pci0000:00/0000:00:1d.0/usb2/2-2/2-2:1.0/video4linux/video1' udev_device_read_db: device 0x21510758 filled with db file data udev_device_new_from_syspath: device 0x21510e10 has devpath '/devices/pci0000:00/0000:00:1d.0/usb2/2-2/2-2:1.0' udev_device_new_from_syspath: device 0x21511b10 has devpath '/devices/pci0000:00/0000:00:1d.0/usb2/2-2' udev_device_new_from_syspath: device 0x215132f8 has devpath '/devices/pci0000:00/0000:00:1d.0/usb2' udev_device_new_from_syspath: device 0x21513650 has devpath '/devices/pci0000:00/0000:00:1d.0' udev_device_new_from_syspath: device 0x21513980 has devpath '/devices/pci0000:00' udev_rules_apply_to_event: GROUP 44 /lib/udev/rules.d/50-udev-default.rules:29 udev_rules_apply_to_event: IMPORT 'v4l_id /dev/video1' /lib/udev/rules.d/60-persistent-v4l.rules:7 udev_event_spawn: starting 'v4l_id /dev/video1' spawn_read: 'v4l_id /dev/video1'(out) 'ID_V4L_VERSION=2' spawn_read: 'v4l_id /dev/video1'(out) 'ID_V4L_PRODUCT=Logitech QuickCam Pro 3000' spawn_read: 'v4l_id /dev/video1'(out) 'ID_V4L_CAPABILITIES=:capture:' spawn_wait: 'v4l_id /dev/video1' [2609] exit with return code 0 udev_rules_apply_to_event: IMPORT builtin 'usb_id' /lib/udev/rules.d/60-persistent-v4l.rules:9 builtin_usb_id: /sys/devices/pci0000:00/0000:00:1d.0/usb2/2-2/2-2:1.0: if_class 10 protocol 0 udev_builtin_add_property: ID_VENDOR=046d udev_builtin_add_property: ID_VENDOR_ENC=046d udev_builtin_add_property: ID_VENDOR_ID=046d udev_builtin_add_property: ID_MODEL=08b0 udev_builtin_add_property: ID_MODEL_ENC=08b0 udev_builtin_add_property: ID_MODEL_ID=08b0 udev_builtin_add_property: ID_REVISION=0002 udev_builtin_add_property: ID_SERIAL=046d_08b0_01402100A5000000 udev_builtin_add_property: ID_SERIAL_SHORT=01402100A5000000 udev_builtin_add_property: ID_TYPE=generic udev_builtin_add_property: ID_BUS=usb udev_builtin_add_property: ID_USB_INTERFACES=:0aff00:010100:010200: udev_builtin_add_property: ID_USB_INTERFACE_NUM=00 udev_builtin_add_property: ID_USB_DRIVER=Philips webcam udev_rules_apply_to_event: LINK 'v4l/by-id/usb-046d_08b0_01402100A5000000-video-index0' /lib/udev/rules.d/60-persistent-v4l.rules:10 udev_rules_apply_to_event: IMPORT builtin 'path_id' /lib/udev/rules.d/60-persistent-v4l.rules:16 udev_builtin_add_property: ID_PATH=pci-0000:00:1d.0-usb-0:2:1.0 udev_builtin_add_property: ID_PATH_TAG=pci-0000_00_1d_0-usb-0_2_1_0 udev_rules_apply_to_event: LINK 'v4l/by-path/pci-0000:00:1d.0-usb-0:2:1.0-video-index0' /lib/udev/rules.d/60-persistent-v4l.rules:17 udev_rules_apply_to_event: RUN 'udev-acl --action=$env{ACTION} --device=$env{DEVNAME}' /lib/udev/rules.d/70-udev-acl.rules:74 udev_rules_apply_to_event: LINK 'webcam1' /etc/udev/rules.d/jj-video.rules:2 udev_event_execute_rules: no node name set, will use kernel supplied name 'video1' udev_node_add: creating device node '/dev/video1', devnum=81:1, mode=0660, uid=0, gid=44 udev_node_mknod: preserve file '/dev/video1', because it has correct dev_t udev_node_mknod: preserve permissions /dev/video1, 020660, uid=0, gid=44 node_symlink: preserve already existing symlink '/dev/char/81:1' to '../video1' link_find_prioritized: found 'c81:2' claiming '/run/udev/links/v4l\x2fby-id\x2fusb-046d_08b0_01402100A5000000-video-index0' udev_device_new_from_syspath: device 0x21516748 has devpath '/devices/pci0000:00/0000:00:1d.1/usb3/3-2/3-2:1.0/video4linux/video2' udev_device_read_db: device 0x21516748 filled with db file data link_find_prioritized: found 'c81:1' claiming '/run/udev/links/v4l\x2fby-id\x2fusb-046d_08b0_01402100A5000000-video-index0' link_update: creating link '/dev/v4l/by-id/usb-046d_08b0_01402100A5000000-video-index0' to '/dev/video1' node_symlink: atomically replace '/dev/v4l/by-id/usb-046d_08b0_01402100A5000000-video-index0' link_find_prioritized: found 'c81:1' claiming '/run/udev/links/v4l\x2fby-path\x2fpci-0000:00:1d.0-usb-0:2:1.0-video-index0' link_update: creating link '/dev/v4l/by-path/pci-0000:00:1d.0-usb-0:2:1.0-video-index0' to '/dev/video1' node_symlink: preserve already existing symlink '/dev/v4l/by-path/pci-0000:00:1d.0-usb-0:2:1.0-video-index0' to '../../video1' link_find_prioritized: found 'c81:1' claiming '/run/udev/links/webcam1' link_update: creating link '/dev/webcam1' to '/dev/video1' node_symlink: preserve already existing symlink '/dev/webcam1' to 'video1' udev_device_update_db: created db file '/run/udev/data/c81:1' for '/devices/pci0000:00/0000:00:1d.0/usb2/2-2/2-2:1.0/video4linux/video1' ACTION=add COLORD_DEVICE=1 COLORD_KIND=camera DEVLINKS=/dev/v4l/by-id/usb-046d_08b0_01402100A5000000-video-index0 /dev/v4l/by-path/pci-0000:00:1d.0-usb-0:2:1.0-video-index0 /dev/webcam1 DEVNAME=/dev/video1 DEVPATH=/devices/pci0000:00/0000:00:1d.0/usb2/2-2/2-2:1.0/video4linux/video1 ID_BUS=usb ID_MODEL=08b0 ID_MODEL_ENC=08b0 ID_MODEL_ID=08b0 ID_PATH=pci-0000:00:1d.0-usb-0:2:1.0 ID_PATH_TAG=pci-0000_00_1d_0-usb-0_2_1_0 ID_REVISION=0002 ID_SERIAL=046d_08b0_01402100A5000000 ID_SERIAL_SHORT=01402100A5000000 ID_TYPE=generic ID_USB_DRIVER=Philips webcam ID_USB_INTERFACES=:0aff00:010100:010200: ID_USB_INTERFACE_NUM=00 ID_V4L_CAPABILITIES=:capture: ID_V4L_PRODUCT=Logitech QuickCam Pro 3000 ID_V4L_VERSION=2 ID_VENDOR=046d ID_VENDOR_ENC=046d ID_VENDOR_ID=046d MAJOR=81 MINOR=1 SUBSYSTEM=video4linux TAGS=:udev-acl: UDEV_LOG=6 USEC_INITIALIZED=18213768 run: 'udev-acl --action=add --device=/dev/video1' jjk@eee-old:~$ (and correspondingly for video2) It looks to me like my rules are read, but not respected. What am I doing wrong?

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  • Special thanks to everyone that helped me in 2010.

    - by mbcrump
    2010 has been a very good year for me and I wanted to create a list and thank everyone for what they have done for me.  I also wanted to thank everyone for reading and subscribing to my blog. It is hard to believe that people actually want to read what I write. I feel like I owe a huge thanks to everyone listed below. Looking back upon 2010, I feel that I’ve grown as a developer and you are part of that reason. Sometimes we get caught up in day to day work and forget to give thanks to those that helped us along the way. The list below is mine, it includes people and companies. This list is obviously not going to include everyone that has helped, just those that have stood out in my mind. When I think back upon 2010, their names keep popping up in my head. So here goes, in no particular order.  People Dave Campbell – For everything he has done for the Silverlight Community with his Silverlight Cream blog. I can’t think of a better person to get recognition at the Silverlight FireStarter event. I also wanted to thank him for spending several hours of his time helping me track down a bug in my feedburner account. Victor Gaudioso – For his large collection of video tutorials on his blog and the passion and enthusiasm he has for Silverlight. We have talked on the phone and I’ve never met anyone so fired up for Silverlight. Kunal Chowdhury – Kunal has always been available for me to bounce ideas off of. Kunal has also answered a lot of questions that stumped me. His blog and CodeProject article have green a great help to me and the Silverlight Community. Glen Gordon – I was looking frantically for a Windows Phone 7 several months before release and Glen found one for me. This allowed me to start a blog series on the Windows Phone 7 hardware and developing an application from start to finish that Scott Guthrie retweeted.  Jeff Blankenburg – For listening to my complaints in the early stages of Windows Phone 7. Jeff was always very polite and gave me his cell phone number to talk it over. He also walked me through several problems that I was having early on. Pete Brown – For writing Silverlight 4 in Action. This book is definitely a labor of love. I followed Pete on Twitter as he was writing it and he spent a lot of late nights and weekends working on it. I felt a lot smarter after reading it the first time. The second time was even better. John Papa – For all of his work on the Silverlight Firestarter and the Silverlight community in general. He has also helped me on a personal level with several things. Daniel Heisler – For putting up with me the past year while we worked on many .NET projects together in 2010. Alvin Ashcraft – For publishing a daily blog post on the best of .NET links. He has linked to my site many times and I really appreciate what he does for the community. Chris Alcock – For publishing the Morning Brew every weekday. I remember when I first appeared on his site, I started getting hundreds of hits on my site and wondered if I was getting a DOS attack or something. It was great to find out that Chris had linked to one of my articles. Joel Cochran – For spending a week teaching “Blend-O-Rama”. This was my one of my favorite sessions of this year. I learned a lot about Expression Blend from it and the best part was that it was free and during lunchtime. Jeremy Likness – Jeremy is smart – very smart. I have learned a lot from Jeremy over the past year. He is also involved in the Silverlight community in every way possible, from forums to blog post to screencast to open source. It goes on and on. The people that I met at VSLive Orlando 2010. I had a great time chatting with Walt Ritscher, Wallace McClure, Tim Huckabee and David Platt. Also a special thanks to all of my friends on Twitter like @wilhil, @DBVaughan, @DataArtist, @wbm, @DirkStrauss and @rsringeri and many many more. Software Companies / Events / May of gave me FREE stuff. =) Microsoft (3) – I was sent a free coupon code by Microsoft to take the Silverlight 4 Beta Exam. I jumped on the offer and took the exam. It was great being selected to try out the exam before it goes public even though Microsoft eventually published a universal coupon code for everyone. I am still waiting to find out if I passed the exam. My fingers are crossed. Microsoft reaching out to me with some questions regarding the .NET Community. I’ve never had a company contact me with such interest in the community. Having a contest where 75 people could win a $100 gift certificate and a T-Shirt for submitting a Windows Phone 7 app. I submitted my app and won. All of the free launch events this year (Windows Phone 7, Visual Studio 2010, ASP.NET MVC). Wintellect – For providing an awesome day of free technical training called T.E.N. Where else can you get free training from some of the best programmers in the world? I also won a contest from them that included a NETAdvantage Ultimate License from Infragistics. VSLive – I attended the Orlando 2010 Conference and it was the best developer’s conference that I have ever attended. I got to know a lot of people at this conference and hang out with many wonderful speakers. I live tweeted the event and while it may have annoyed some, the organizers of VSLive loved it. I won the contest on Twitter and they invited me back to the 2011 session of my choice. This is a very nice gift and I really appreciate the generosity. BarcodeLib.com – For providing free barcode generating tools for a Non-Profit ASP.NET project that I was working on. Their third party controls really made this a breeze compared to my existing solution. NDepend – It is absolutely the best tool to improve code quality. The product is extremely large and I would recommend heading over to their site to check it out. Silverlight Spy – I was writing a blog post on Silverlight Spy and Koen Zwikstra provided a FREE license to me. If you ever wanted to peek inside of a Silverlight Application then this is the tool for you. He is also working on a version that will support OOB and Windows Phone 7. I would recommend checking out his site. Birmingham .NET Users Group / Silverlight Nights User Group – It takes a lot of time to put together a user group meeting every month yet it always seems to happen. I don’t want to name names for fear of leaving someone out but both of these User Groups are excellent if you live in the Birmingham, Alabama area. Publishing Companies Manning Publishing – For giving me early access to Silverlight 4 in Action by Pete Brown. It was really nice to be able to read this awesome book while Pete was writing it. I was also one of the first people to publish a review of the book. Sams Publishing and DZone – For providing a copy of Silverlight 4 Unleashed by Laurent Bugnion for me to review for their site. The review is coming in January 2011. Special Shoutout to the following 3rd Party Silverlight Controls It has been a great pleasure to work with the following companies on 3rd Party Control Giveaways every month. It always amazes me how every 3rd Party Control company is so eager to help out the community. I’ve never been turned down by any of these companies! These giveaways have sparked a lot of interest in Silverlight and hopefully I can continue giving away a new set every month. If you are a 3rd Party Control company and are interested in participating in these giveaways then please email me at mbcrump29[at]gmail[d0t].com. The companies below have already participated in my giveaways: Infragistics (December 2010) - Win a set of Infragistics Silverlight Controls with Data Visualization!  Mindscape (November 2010) - Mindscape Silverlight Controls + Free Mega Pack Contest Telerik (October 2010) - Win Telerik RadControls for Silverlight! ($799 Value) Again, I just wanted to say Thanks to everyone for helping me grow as a developer.  Subscribe to my feed

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  • Why version of chrome does not matter much more then firefox and firefox does not matter much as IE

    - by anirudha
    Everything not perfect. in software the software make and growth by user feedback like what user expected from the software and want in next version of software. In a chrome Event i hear about the Chromium. you can find some interesting things here Video 1 Video 2 come to the point. when i hear about some good website of india. many of them talking a little thing in common that. We are #1 because we not thing that we make a great application and deploy them and think that we finished own works preharps in a small days we make a small website deploy them and improve them always latter. what the point they all talking about:- the conclusion is that software make by user feedback. they tell that he not spent much time and wait for a long time when their project was finish and they launch their website. preharps they tell that they make a small website in a small time and launched them. make a research on them later and make them better later and website growth as they thing. if they are late then someone else can win even their project was much good them other. not more but a little story:-  before few month i hear about a great website who sold many of books daily i myself purchase some from them to track how they work and how they provided service. i not found any problem with their service. the service they provided is good but when i see their website i found that the mockup code was very badly designed. i am not know the matter how they growth because they used very other stuff who make their website slow. when i research something more i found that their is very hard to implement the website look like them. on their blog they writing about a mail they have. the clone of them make by many other but not goes good as well as they make. after few month later website is looking great. many thing they improved and make them better as  other thing. a another conclusion that same as another story that user feedback. well now come to the point. we talking about Chrome,firefox and IE. what thing is goes common that they all are browser. but something goes different that Chrome is a one of the best browser. from a month many of issue submitted to chrome that user found when they use them. so what is make this different the different is that when feedback goes to someone they take a action and think to make them better so improvement of chrome based on feedback user put using many things. secondly because it's goes open-source many of developer contribute them and make them real browser not real [tape] browser as like IE [a good example]. as you see in video they talking about silent update in chrome and futurecoming chromium. the thing they implement is too good. because by this thing user not worry about a new version. i myself never find a problem that you need to user new version as we found same problem in other application. Well think are great in chrome and now talking about Firefox. Firefox is a best option for development as well as chrome best for surfing the internet. in firefox many thing are great like plugin [ex: Firebug] , addons personas themes and many other thing and customization in firefox make them really a browser not like a joker [IE a good example]. well now come to IE. are IE really great no. someone from Microsoft can say that ha ha hi hi because they can't see the power of open-source. they thing that they make a software and they never need user feedback because they produced windows who really great for user because they used them. example :- before few month Microsoft shipped Windows live. when i use them that i found that their is no sense make for using this one software. suppose you need to write a post through Live writer. the old version are great i myself have no problem but in 2011 i found that they changed everything in user interface. so learn a new thing and spent sometime more to learn a new version whenever need are same and feature are same so why user spent a little time more to learn a lesson who they want to teach even their is no sense to learn them. the problem in 2011 Live not only of mine their are many other have same problem as mine and forget live 2011 after the see a badly design user interface. even they tell we maked in WPF yeah yeah WPF we make in .net. are you can say that what is the matter .net for user. the user have no problem to use WPF based application even you make them fool as we make them in WPF 2020 they are future technologies and we launch it 10 year before only for you yeah you dear customer of mine. yeah they thing WPF is best and thing to implement every software they make even they forget to make better user interface but they also remember to make them next version in WPF. the IE 9 Rc release on 10 febuary. but are they really cool. how much feedback they take and take action of them. their is no answer because they thing to launch a software they never thing what user want and off-course not care of user feedback. as we mention in Firefox and in chrome user feedback have a big matter because sound come from a public and user who use the software not only who make them software as IE 9 have. so feedback take a opportunities to make their software better and less hassel to use them in user hands not only in developer hands. so IE9 is not a good guys who still need of user if they really want a experience. well what Microsoft implemented in IE. i am not talking about that furthure more but i found in article last days[why not say reading a google blog]  yeah see them in http://googleblog.blogspot.com/2011/02/microsofts-bing-uses-google-search.html Well their is nothing good for developer in IE9. the blah blah blah they can always said on MSDN and many other site they have. many from public talking about them because they never can see a good software outside Microsoft. they never talking about Firebug even in books they never show you that. well i know competitor never show you a stuff of competitor i have same issue from Yahoo. on a days i hear from newsletter from them they write a subline on the bottom that USE IE or Firefox to exerience better Web. i am agree with Firefox and i am not know they really talking about IE or joking but i never believe they forget to put chrome. well i know their is corporate rule everyone should follow first. so no problem yahoo i know the matter. well IE:- so what is IE and Why We should use IE. well their is no sense to use IE. the thing we expect from IE but never found that:- first thing is that as a developer we thing the customization as well as other browser have like in chrome have it's own customization and firefox is also great in this matter. but IE really for Web development. are you joking:- the thing they mention in their blog is that IE9 have a new developer tool who have three new panel or tabs. are this joke whenever Firefox and chrome have everyday a new plugin or great upgrade of old plugin they tell we add three new panel first is network second is blah third is blah. well nice joke you make all MSDN blogger i like the way you talking about IE.  even we know what matter the browser have. i thing whenever they make IE 6 they talking about IE as same as they talking today. Secondly their is no other tool to use with IE deveoper tool like Firebug is avilable in IE but not make by IE. firebug team themselves make them for IE. because many of developer thing to use firebug but can't use because they still goes mad about IE because day and night they only hear about tools maked by Microsoft. so no plugin [even very small developer tool] no customized no personas on themse. no update yeah why forget these topic come with us and share a little thing more. IE launch IE 6 after 7 after 8 and now 9 [even in future] but what they do. they do nothing on user feedback they still thing WPF is great because colors make user cool and they forget to implement other things as other already provide. Chrome and Firefox are come after IE. Mozilla firefox come in 2004 and chrome is late in 2008. even they are late they still focus on Developer and thing they feel first is that customization like developer tool , themese and perfsonas and many other great things. are they can find in IE even next i means 10 yeah IE10 never because they thing only making a software or force user to use new version of OS. i am confused that why not wait and force user to purchase windows 8 instead of 7. so IE have no customization even small developer tool i thing that they make a customizable interface like in firefox who configure by about:config. so thing is discussed about really not a point we thing to goes but now it's clear what is making no matter for version in Firefox and chrome. because chrome and firefox not wait for  a long time and explode a bomb to make publicity. they still work and make upgrade possible to user as soon as possible. [chrome never tell about they goes old they himself update them].so update comes soon in Firefox and in chrome but in IE their is a long time to wait and they make them without feedback. so IE really not for human and not really for us. whenver you found a bug in chrome and in firefox you report them and found that they are work in progressed and can be see in next version of firefox. but what you see whenever you see IE. you found that what the bug can found in IE whenver they not implemented same feature in IE. well IE 9 is next IE6 for developer. conclusion:-  after reading a whole post you find that i hate all thing about IE. why are i write a big post on a small pity software IE. why i open the poll of IE. are their anything in IE break my heart. are their is something goes wrong with me and with my IE9. are their is anything i got with IE9. why i write a big post. well as a developer play a trick that give sometime to chrome to make them better and some other to make firefox better and feel something you contribute really have a matter as a contribute you find some other and their thought on same software. some are great maybe some of them blah blah. but are their is true that outside Microsoft their is no good sollution can make because it's outside Microsoft. their is not true. the thing developer make not have matter even using Microsoft technologies or outside technologies of MS. so stop this i not want to talking some other things just stop it. i means their is no more blah i want to talking with you for IE.i still hate them and believe it is next IE6 for Web. Answers: if you still need a answer in lines that the answer is that IE late update as long as they can and also make force user to upgrade IE9 because they want to promote windows first then thing about IE and chrome and firefox not do that as same as IE. so IE is late and user forced software. in firefox and chrome upgrade come soon as soon as they possible. Thanks to give me a great time and red my blah on Blah i means IE9 Thanks again Anirudha

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  • Optimizing Solaris 11 SHA-1 on Intel Processors

    - by danx
    SHA-1 is a "hash" or "digest" operation that produces a 160 bit (20 byte) checksum value on arbitrary data, such as a file. It is intended to uniquely identify text and to verify it hasn't been modified. Max Locktyukhin and others at Intel have improved the performance of the SHA-1 digest algorithm using multiple techniques. This code has been incorporated into Solaris 11 and is available in the Solaris Crypto Framework via the libmd(3LIB), the industry-standard libpkcs11(3LIB) library, and Solaris kernel module sha1. The optimized code is used automatically on systems with a x86 CPU supporting SSSE3 (Intel Supplemental SSSE3). Intel microprocessor architectures that support SSSE3 include Nehalem, Westmere, Sandy Bridge microprocessor families. Further optimizations are available for microprocessors that support AVX (such as Sandy Bridge). Although SHA-1 is considered obsolete because of weaknesses found in the SHA-1 algorithm—NIST recommends using at least SHA-256, SHA-1 is still widely used and will be with us for awhile more. Collisions (the same SHA-1 result for two different inputs) can be found with moderate effort. SHA-1 is used heavily though in SSL/TLS, for example. And SHA-1 is stronger than the older MD5 digest algorithm, another digest option defined in SSL/TLS. Optimizations Review SHA-1 operates by reading an arbitrary amount of data. The data is read in 512 bit (64 byte) blocks (the last block is padded in a specific way to ensure it's a full 64 bytes). Each 64 byte block has 80 "rounds" of calculations (consisting of a mixture of "ROTATE-LEFT", "AND", and "XOR") applied to the block. Each round produces a 32-bit intermediate result, called W[i]. Here's what each round operates: The first 16 rounds, rounds 0 to 15, read the 512 bit block 32 bits at-a-time. These 32 bits is used as input to the round. The remaining rounds, rounds 16 to 79, use the results from the previous rounds as input. Specifically for round i it XORs the results of rounds i-3, i-8, i-14, and i-16 and rotates the result left 1 bit. The remaining calculations for the round is a series of AND, XOR, and ROTATE-LEFT operators on the 32-bit input and some constants. The 32-bit result is saved as W[i] for round i. The 32-bit result of the final round, W[79], is the SHA-1 checksum. Optimization: Vectorization The first 16 rounds can be vectorized (computed in parallel) because they don't depend on the output of a previous round. As for the remaining rounds, because of step 2 above, computing round i depends on the results of round i-3, W[i-3], one can vectorize 3 rounds at-a-time. Max Locktyukhin found through simple factoring, explained in detail in his article referenced below, that the dependencies of round i on the results of rounds i-3, i-8, i-14, and i-16 can be replaced instead with dependencies on the results of rounds i-6, i-16, i-28, and i-32. That is, instead of initializing intermediate result W[i] with: W[i] = (W[i-3] XOR W[i-8] XOR W[i-14] XOR W[i-16]) ROTATE-LEFT 1 Initialize W[i] as follows: W[i] = (W[i-6] XOR W[i-16] XOR W[i-28] XOR W[i-32]) ROTATE-LEFT 2 That means that 6 rounds could be vectorized at once, with no additional calculations, instead of just 3! This optimization is independent of Intel or any other microprocessor architecture, although the microprocessor has to support vectorization to use it, and exploits one of the weaknesses of SHA-1. Optimization: SSSE3 Intel SSSE3 makes use of 16 %xmm registers, each 128 bits wide. The 4 32-bit inputs to a round, W[i-6], W[i-16], W[i-28], W[i-32], all fit in one %xmm register. The following code snippet, from Max Locktyukhin's article, converted to ATT assembly syntax, computes 4 rounds in parallel with just a dozen or so SSSE3 instructions: movdqa W_minus_04, W_TMP pxor W_minus_28, W // W equals W[i-32:i-29] before XOR // W = W[i-32:i-29] ^ W[i-28:i-25] palignr $8, W_minus_08, W_TMP // W_TMP = W[i-6:i-3], combined from // W[i-4:i-1] and W[i-8:i-5] vectors pxor W_minus_16, W // W = (W[i-32:i-29] ^ W[i-28:i-25]) ^ W[i-16:i-13] pxor W_TMP, W // W = (W[i-32:i-29] ^ W[i-28:i-25] ^ W[i-16:i-13]) ^ W[i-6:i-3]) movdqa W, W_TMP // 4 dwords in W are rotated left by 2 psrld $30, W // rotate left by 2 W = (W >> 30) | (W << 2) pslld $2, W_TMP por W, W_TMP movdqa W_TMP, W // four new W values W[i:i+3] are now calculated paddd (K_XMM), W_TMP // adding 4 current round's values of K movdqa W_TMP, (WK(i)) // storing for downstream GPR instructions to read A window of the 32 previous results, W[i-1] to W[i-32] is saved in memory on the stack. This is best illustrated with a chart. Without vectorization, computing the rounds is like this (each "R" represents 1 round of SHA-1 computation): RRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRR With vectorization, 4 rounds can be computed in parallel: RRRRRRRRRRRRRRRRRRRR RRRRRRRRRRRRRRRRRRRR RRRRRRRRRRRRRRRRRRRR RRRRRRRRRRRRRRRRRRRR Optimization: AVX The new "Sandy Bridge" microprocessor architecture, which supports AVX, allows another interesting optimization. SSSE3 instructions have two operands, a input and an output. AVX allows three operands, two inputs and an output. In many cases two SSSE3 instructions can be combined into one AVX instruction. The difference is best illustrated with an example. Consider these two instructions from the snippet above: pxor W_minus_16, W // W = (W[i-32:i-29] ^ W[i-28:i-25]) ^ W[i-16:i-13] pxor W_TMP, W // W = (W[i-32:i-29] ^ W[i-28:i-25] ^ W[i-16:i-13]) ^ W[i-6:i-3]) With AVX they can be combined in one instruction: vpxor W_minus_16, W, W_TMP // W = (W[i-32:i-29] ^ W[i-28:i-25] ^ W[i-16:i-13]) ^ W[i-6:i-3]) This optimization is also in Solaris, although Sandy Bridge-based systems aren't widely available yet. As an exercise for the reader, AVX also has 256-bit media registers, %ymm0 - %ymm15 (a superset of 128-bit %xmm0 - %xmm15). Can %ymm registers be used to parallelize the code even more? Optimization: Solaris-specific In addition to using the Intel code described above, I performed other minor optimizations to the Solaris SHA-1 code: Increased the digest(1) and mac(1) command's buffer size from 4K to 64K, as previously done for decrypt(1) and encrypt(1). This size is well suited for ZFS file systems, but helps for other file systems as well. Optimized encode functions, which byte swap the input and output data, to copy/byte-swap 4 or 8 bytes at-a-time instead of 1 byte-at-a-time. Enhanced the Solaris mdb(1) and kmdb(1) debuggers to display all 16 %xmm and %ymm registers (mdb "$x" command). Previously they only displayed the first 8 that are available in 32-bit mode. Can't optimize if you can't debug :-). Changed the SHA-1 code to allow processing in "chunks" greater than 2 Gigabytes (64-bits) Performance I measured performance on a Sun Ultra 27 (which has a Nehalem-class Xeon 5500 Intel W3570 microprocessor @3.2GHz). Turbo mode is disabled for consistent performance measurement. Graphs are better than words and numbers, so here they are: The first graph shows the Solaris digest(1) command before and after the optimizations discussed here, contained in libmd(3LIB). I ran the digest command on a half GByte file in swapfs (/tmp) and execution time decreased from 1.35 seconds to 0.98 seconds. The second graph shows the the results of an internal microbenchmark that uses the Solaris libpkcs11(3LIB) library. The operations are on a 128 byte buffer with 10,000 iterations. The results show operations increased from 320,000 to 416,000 operations per second. Finally the third graph shows the results of an internal kernel microbenchmark that uses the Solaris /kernel/crypto/amd64/sha1 module. The operations are on a 64Kbyte buffer with 100 iterations. third graph shows the results of an internal kernel microbenchmark that uses the Solaris /kernel/crypto/amd64/sha1 module. The operations are on a 64Kbyte buffer with 100 iterations. The results show for 1 kernel thread, operations increased from 410 to 600 MBytes/second. For 8 kernel threads, operations increase from 1540 to 1940 MBytes/second. Availability This code is in Solaris 11 FCS. It is available in the 64-bit libmd(3LIB) library for 64-bit programs and is in the Solaris kernel. You must be running hardware that supports Intel's SSSE3 instructions (for example, Intel Nehalem, Westmere, or Sandy Bridge microprocessor architectures). The easiest way to determine if SSSE3 is available is with the isainfo(1) command. For example, nehalem $ isainfo -v $ isainfo -v 64-bit amd64 applications sse4.2 sse4.1 ssse3 popcnt tscp ahf cx16 sse3 sse2 sse fxsr mmx cmov amd_sysc cx8 tsc fpu 32-bit i386 applications sse4.2 sse4.1 ssse3 popcnt tscp ahf cx16 sse3 sse2 sse fxsr mmx cmov sep cx8 tsc fpu If the output also shows "avx", the Solaris executes the even-more optimized 3-operand AVX instructions for SHA-1 mentioned above: sandybridge $ isainfo -v 64-bit amd64 applications avx xsave pclmulqdq aes sse4.2 sse4.1 ssse3 popcnt tscp ahf cx16 sse3 sse2 sse fxsr mmx cmov amd_sysc cx8 tsc fpu 32-bit i386 applications avx xsave pclmulqdq aes sse4.2 sse4.1 ssse3 popcnt tscp ahf cx16 sse3 sse2 sse fxsr mmx cmov sep cx8 tsc fpu No special configuration or setup is needed to take advantage of this code. Solaris libraries and kernel automatically determine if it's running on SSSE3 or AVX-capable machines and execute the correctly-tuned code for that microprocessor. Summary The Solaris 11 Crypto Framework, via the sha1 kernel module and libmd(3LIB) and libpkcs11(3LIB) libraries, incorporated a useful SHA-1 optimization from Intel for SSSE3-capable microprocessors. As with other Solaris optimizations, they come automatically "under the hood" with the current Solaris release. References "Improving the Performance of the Secure Hash Algorithm (SHA-1)" by Max Locktyukhin (Intel, March 2010). The source for these SHA-1 optimizations used in Solaris "SHA-1", Wikipedia Good overview of SHA-1 FIPS 180-1 SHA-1 standard (FIPS, 1995) NIST Comments on Cryptanalytic Attacks on SHA-1 (2005, revised 2006)

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  • Windows 8 Will be Here Tomorrow; but Should Silverlight be Gone Today?

    - by andrewbrust
    The software industry lives within an interesting paradox. IT in the enterprise moves slowly and cautiously, upgrading only when safe and necessary.  IT interests intentionally live in the past.  On the other hand, developers, and Independent Software Vendors (ISVs) not only want to use the latest and greatest technologies, but this constituency prides itself on gauging tech’s future, and basing its present-day strategy upon it.  Normally, we as an industry manage this paradox with a shrug of the shoulder and musings along the lines of “it takes all kinds.”  Different subcultures have different tendencies.  So be it. Microsoft, with its Windows operating system (OS), can’t take such a laissez-faire view of the world though.  Redmond relies on IT to deploy Windows and (at the very least) influence its procurement, but it also relies on developers to build software for Windows, especially software that has a dependency on features in new versions of the OS.  It must indulge and nourish developers’ fetish for an early birthing of the next generation of software, even as it acknowledges the IT reality that the next wave will arrive on-schedule in Redmond and will travel very slowly to end users. With the move to Windows 8, and the corresponding shift in application development models, this paradox is certainly in place. On the one hand, the next version of Windows is widely expected sometime in 2012, and its full-scale deployment will likely push into 2014 or even later.  Meanwhile, there’s a technology that runs on today’s Windows 7, will continue to run in the desktop mode of Windows 8 (the next version’s codename), and provides absolutely the best architectural bridge to the Windows 8 Metro-style application development stack.  That technology is Silverlight.  And given what we now know about Windows 8, one might think, as I do, that Microsoft ecosystem developers should be flocking to it. But because developers are trying to get a jump on the future, and since many of them believe the impending v5.0 release of Silverlight will be the technology’s last, not everyone is flocking to it; in fact some are fleeing from it.  Is this sensible?  Is it not unprecedented?  What options does it lead to?  What’s the right way to think about the situation? Is v5.0 really the last major version of the technology called Silverlight?  We don’t know.  But Scott Guthrie, the “father” and champion of the technology, left the Developer Division of Microsoft months ago to work on the Windows Azure team, and he took his people with him.  John Papa, who was a very influential Redmond-based evangelist for Silverlight (and is a Visual Studio Magazine author), left Microsoft completely.  About a year ago, when initial suspicion of Silverlight’s demise reached significant magnitude, Papa interviewed Guthrie on video and their discussion served to dispel developers’ fears; but now they’ve moved on. So read into that what you will and let’s suppose, for the sake of argument, speculation that Silverlight’s days of major revision and iteration are over now is correct.  Let’s assume the shine and glimmer has dimmed.  Let’s assume that any Silverlight application written today, and that therefore any investment of financial and human resources made in Silverlight development today, is destined for rework and extra investment in a few years, if the application’s platform needs to stay current. Is this really so different from any technology investment we make?  Every framework, language, runtime and operating system is subject to change, to improvement, to flux and, yes, to obsolescence.  What differs from project to project, is how near-term that obsolescence is and how disruptive the change will be.  The shift from .NET 1.1. to 2.0 was incremental.  Some of the further changes were too.  But the switch from Windows Forms to WPF was major, and the change from ASP.NET Web Services (asmx) to Windows Communication Foundation (WCF) was downright fundamental. Meanwhile, the transition to the .NET development model for Windows 8 Metro-style applications is actually quite gentle.  The finer points of this subject are covered nicely in Magenic’s excellent white paper “Assessing the Windows 8 Development Platform.” As the authors of that paper (including Rocky Lhotka)  point out, Silverlight code won’t just “port” to Windows 8.  And, no, Silverlight user interfaces won’t either; Metro always supports XAML, but that relationship is not commutative.  But the concepts, the syntax, the architecture and developers’ skills map from Silverlight to Windows 8 Metro and the Windows Runtime (WinRT) very nicely.  That’s not a coincidence.  It’s not an accident.  This is a protected transition.  It’s not a slap in the face. There are few things that are unnerving about this transition, which make it seem markedly different from others: The assumed end of the road for Silverlight is something many think they can see.  Instead of being ignorant of the technology’s expiration date, we believe we know it.  If ignorance is bliss, it would seem our situation lacks it. The new technology involving WinRT and Metro involves a name change from Silverlight. .NET, which underlies both Silverlight and the XAML approach to WinRT development, has just about reached 10 years of age.  That’s equivalent to 80 in human years, or so many fear. My take is that the combination of these three factors has contributed to what for many is a psychologically compelling case that Silverlight should be abandoned today and HTML 5 (the agnostic kind, not the Windows RT variety) should be embraced in its stead.  I understand the logic behind that.  I appreciate the preemptive, proactive, vigilant conscientiousness involved in its calculus.  But for a great many scenarios, I don’t agree with it.  HTML 5 clients, no matter how impressive their interactivity and the emulation of native application interfaces they present may be, are still second-class clients.  They are getting better, especially when hardware acceleration and fast processors are involved.  But they still lag.  They still feel like they’re emulating something, like they’re prototypes, like they’re not comfortable in their own skins.  They are based on compromise, and they feel compromised too. HTML 5/JavaScript development tools are getting better, and will get better still, but they are not as productive as tools for other environments, like Flash, like Silverlight or even more primitive tooling for iOS or Android.  HTML’s roots as a document markup language, rather than an application interface, create a disconnect that impedes productivity.  I do not necessarily think that problem is insurmountable, but it’s here today. If you’re building line-of-business applications, you need a first-class client and you need productivity.  Lack of productivity increases your costs and worsens your backlog.  A second class client will erode user satisfaction, which is never good.  Worse yet, this erosion will be inconspicuous, rather than easily identified and diagnosed, because the inferiority of an HTML 5 client over a native one is hard to identify and, notably, doing so at this juncture in the industry is unpopular.  Why would you fault a technology that everyone believes is revolutionary?  Instead, user disenchantment will remain latent and yet will add to the malaise caused by slower development. If you’re an ISV and you’re coveting the reach of running multi-platform, it’s a different story.  You’ve likely wanted to move to HTML 5 already, and the uncertainty around Silverlight may be the only remaining momentum or pretext you need to make the shift.  You’re deploying many more copies of your application than a line-of-business developer is anyway; this makes the economic hit from lower productivity less impactful, and the wider potential installed base might even make it profitable. But no matter who you are, it’s important to take stock of the situation and do it accurately.  Continued, but merely incremental changes in a development model lead to conservatism and general lack of innovation in the underlying platform.  Periods of stability and equilibrium are necessary, but permanence in that equilibrium leads to loss of platform relevance, market share and utility.  Arguably, that’s already happened to Windows.  The change Windows 8 brings is necessary and overdue.  The marked changes in using .NET if we’re to build applications for the new OS are inevitable.  We will ultimately benefit from the change, and what we can reasonably hope for in the interim is a migration path for our code and skills that is navigable, logical and conceptually comfortable. That path takes us to a place called WinRT, rather than a place called Silverlight.  But considering everything that is changing for the good, the number of disruptive changes is impressively minimal.  The name may be changing, and there may even be some significance to that in terms of Microsoft’s internal management of products and technologies.  But as the consumer, you should care about the ingredients, not the name.  Turkish coffee and Greek coffee are much the same. Although you’ll find plenty of interested parties who will find the names significant, drinkers of the beverage should enjoy either one.  It’s all coffee, it’s all sweet, and you can tell your fortune from the grounds that are left at the end.  Back on the software side, it’s all XAML, and C# or VB .NET, and you can make your fortune from the product that comes out at the end.  Coffee drinkers wouldn’t switch to tea.  Why should XAML developers switch to HTML?

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  • Software Engineering Practices &ndash; Different Projects should have different maturity levels

    - by Dylan Smith
    I’ve had a lot of discussions at the office lately about the drastically different sets of software engineering practices used on our various projects, if what we are doing is appropriate, and what factors should you be considering when determining what practices are most appropriate in a given context. I wanted to write up my thoughts in a little more detail on this subject, so here we go: If you compare any two software projects (specifically comparing their codebases) you’ll often see very different levels of maturity in the software engineering practices employed. By software engineering practices, I’m specifically referring to the quality of the code and the amount of technical debt present in the project. Things such as Test Driven Development, Domain Driven Design, Behavior Driven Development, proper adherence to the SOLID principles, etc. are all practices that you would expect at the mature end of the spectrum. At the other end of the spectrum would be the quick-and-dirty solutions that are done using something like an Access Database, Excel Spreadsheet, or maybe some quick “drag-and-drop coding”. For this blog post I’m going to refer to this as the Software Engineering Maturity Spectrum (SEMS). I believe there is a time and a place for projects at every part of that SEMS. The risks and costs associated with under-engineering solutions have been written about a million times over so I won’t bother going into them again here, but there are also (unnecessary) costs with over-engineering a solution. Sometimes putting multiple layers, and IoC containers, and abstracting out the persistence, etc is complete overkill if a one-time use Access database could solve the problem perfectly well. A lot of software developers I talk to seem to automatically jump to the very right-hand side of this SEMS in everything they do. A common rationalization I hear is that it may seem like a small trivial application today, but these things always grow and stick around for many years, then you’re stuck maintaining a big ball of mud. I think this is a cop-out. Sure you can’t always anticipate how an application will be used or grow over its lifetime (can you ever??), but that doesn’t mean you can’t manage it and evolve the underlying software architecture as necessary (even if that means having to toss the code out and re-write it at some point…maybe even multiple times). My thoughts are that we should be making a conscious decision around the start of each project approximately where on the SEMS we want the project to exist. I believe this decision should be based on 3 factors: 1. Importance - How important to the business is this application? What is the impact if the application were to suddenly stop working? 2. Complexity - How complex is the application functionality? 3. Life-Expectancy - How long is this application expected to be in use? Is this a one-time use application, does it fill a short-term need, or is it more strategic and is expected to be in-use for many years to come? Of course this isn’t an exact science. You can’t say that Project X should be at the 73% mark on the SEMS and expect that to be helpful. My point is not that you need to precisely figure out what point on the SEMS the project should be at then translate that into some prescriptive set of practices and techniques you should be using. Rather my point is that we need to be aware that there is a spectrum, and that not everything is going to be (or should be) at the edges of that spectrum, indeed a large number of projects should probably fall somewhere within the middle; and different projects should adopt a different level of software engineering practices and maturity levels based on the needs of that project. To give an example of this way of thinking from my day job: Every couple of years my company plans and hosts a large event where ~400 of our customers all fly in to one location for a multi-day event with various activities. We have some staff whose job it is to organize the logistics of this event, which includes tracking which flights everybody is booked on, arranging for transportation to/from airports, arranging for hotel rooms, name tags, etc The last time we arranged this event all these various pieces of data were tracked in separate spreadsheets and reconciliation and cross-referencing of all the data was literally done by hand using printed copies of the spreadsheets and several people sitting around a table going down each list row by row. Obviously there is some room for improvement in how we are using software to manage the event’s logistics. The next time this event occurs we plan to provide the event planning staff with a more intelligent tool (either an Excel spreadsheet or probably an Access database) that can track all the information in one location and make sure that the various pieces of data are properly linked together (so for example if a person cancels you only need to delete them from one place, and not a dozen separate lists). This solution would fall at or near the very left end of the SEMS meaning that we will just quickly create something with very little attention paid to using mature software engineering practices. If we examine this project against the 3 criteria I listed above for determining it’s place within the SEMS we can see why: Importance – If this application were to stop working the business doesn’t grind to a halt, revenue doesn’t stop, and in fact our customers wouldn’t even notice since it isn’t a customer facing application. The impact would simply be more work for our event planning staff as they revert back to the previous way of doing things (assuming we don’t have any data loss). Complexity – The use cases for this project are pretty straightforward. It simply needs to manage several lists of data, and link them together appropriately. Precisely the task that access (and/or Excel) can do with minimal custom development required. Life-Expectancy – For this specific project we’re only planning to create something to be used for the one event (we only hold these events every 2 years). If it works well this may change (see below). Let’s assume we hack something out quickly and it works great when we plan the next event. We may decide that we want to make some tweaks to the tool and adopt it for planning all future events of this nature. In that case we should examine where the current application is on the SEMS, and make a conscious decision whether something needs to be done to move it further to the right based on the new objectives and goals for this application. This may mean scrapping the access database and re-writing it as an actual web or windows application. In this case, the life-expectancy changed, but let’s assume the importance and complexity didn’t change all that much. We can still probably get away with not adopting a lot of the so-called “best practices”. For example, we can probably still use some of the RAD tooling available and might have an Autonomous View style design that connects directly to the database and binds to typed datasets (we might even choose to simply leave it as an access database and continue using it; this is a decision that needs to be made on a case-by-case basis). At Anvil Digital we have aspirations to become a primarily product-based company. So let’s say we use this tool to plan a handful of events internally, and everybody loves it. Maybe a couple years down the road we decide we want to package the tool up and sell it as a product to some of our customers. In this case the project objectives/goals change quite drastically. Now the tool becomes a source of revenue, and the impact of it suddenly stopping working is significantly less acceptable. Also as we hold focus groups, and gather feedback from customers and potential customers there’s a pretty good chance the feature-set and complexity will have to grow considerably from when we were using it only internally for planning a small handful of events for one company. In this fictional scenario I would expect the target on the SEMS to jump to the far right. Depending on how we implemented the previous release we may be able to refactor and evolve the existing codebase to introduce a more layered architecture, a robust set of automated tests, introduce a proper ORM and IoC container, etc. More likely in this example the jump along the SEMS would be so large we’d probably end up scrapping the current code and re-writing. Although, if it was a slow phased roll-out to only a handful of customers, where we collected feedback, made some tweaks, and then rolled out to a couple more customers, we may be able to slowly refactor and evolve the code over time rather than tossing it out and starting from scratch. The key point I’m trying to get across is not that you should be throwing out your code and starting from scratch all the time. But rather that you should be aware of when and how the context and objectives around a project changes and periodically re-assess where the project currently falls on the SEMS and whether that needs to be adjusted based on changing needs. Note: There is also the idea of “spectrum decay”. Since our industry is rapidly evolving, what we currently accept as mature software engineering practices (the right end of the SEMS) probably won’t be the same 3 years from now. If you have a project that you were to assess at somewhere around the 80% mark on the SEMS today, but don’t touch the code for 3 years and come back and re-assess its position, it will almost certainly have changed since the right end of the SEMS will have moved farther out (maybe the project is now only around 60% due to decay). Developer Skills Another important aspect to this whole discussion is around the skill sets of your architects and lead developers. When talking about the progression of a developers skills from junior->intermediate->senior->… they generally start by only being able to write code that belongs on the left side of the SEMS and as they gain more knowledge and skill they become capable of working at a higher and higher level along the SEMS. We all realize that the learning never stops, but eventually you’ll get to the point where you can comfortably develop at the right-end of the SEMS (the exact practices and techniques that translates to is constantly changing, but that’s not the point here). A critical skill that I’d love to see more evidence of in our industry is the most senior guys not only being able to work at the right-end of the SEMS, but more importantly be able to consciously work at any point along the SEMS as project needs dictate. An even more valuable skill would be if you could make the conscious decision to move a projects code further right on the SEMS (based on changing needs) and do so in an incremental manner without having to start from scratch. An exercise that I’m planning to go through with all of our projects here at Anvil in the near future is to map out where I believe each project currently falls within this SEMS, where I believe the project *should* be on the SEMS based on the business needs, and for those that don’t match up (i.e. most of them) come up with a plan to improve the situation.

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  • Click Once Deployment Process and Issue Resolution

    - by Geordie
    Introduction We are adopting Click Once as a deployment standard for Thick .Net application clients.  The latest version of this tool has matured it to a point where it can be used in an enterprise environment.  This guide will identify how to use Click Once deployment and promote code trough the dev, test and production environments. Why Use Click Once over SCCM If we already use SCCM why add Click Once to the deployment options.  The advantages of Click Once are their ability to update the code in a single location and have the update flow automatically down to the user community.  There have been challenges in the past with getting configuration updates to download but these can now be achieved.  With SCCM you can do the same thing but it then needs to be packages and pushed out to users.  Each time a new user is added to an application, time needs to be spent by an administrator, to push out any required application packages.  With Click Once the user would go to a web link and the application and pre requisites will automatically get installed. New Deployment Steps Overview The deployment in an enterprise environment includes several steps as the solution moves through the development life cycle before being released into production.  To make mitigate risk during the release phase, it is important to ensure the solution is not deployed directly into production from the development tools.  Although this is the easiest path, it can introduce untested code into production and result in unexpected results. 1. Deploy the client application to a development web server using Visual Studio 2008 Click Once deployment tools.  Once potential production versions of the solution are being generated, ensure the production install URL is specified when deploying code from Visual Studio.  (For details see ‘Deploying Click Once Code from Visual Studio’) 2. xCopy the code to the test server.  Run the MageUI tool to update the URLs, signing and version numbers to match the test server. (For details see ‘Moving Click Once Code to a new Server without using Visual Studio’) 3. xCopy the code to the production server.  Run the MageUI tool to update the URLs, signing and version numbers to match the production server. The certificate used to sign the code should be provided by a certificate authority that will be trusted by the client machines.  Finally make sure the setup.exe contains the production install URL.  If not redeploy the solution from Visual Studio to the dev environment specifying the production install URL.  Then xcopy the install.exe file from dev to production.  (For details see ‘Moving Click Once Code to a new Server without using Visual Studio’) Detailed Deployment Steps Deploying Click Once Code From Visual Studio Open Visual Studio and create a new WinForms or WPF project.   In the solution explorer right click on the project and select ‘Publish’ in the context menu.   The ‘Publish Wizard’ will start.  Enter the development deployment path.  This could be a local directory or web site.  When first publishing the solution set this to a development web site and Visual basic will create a site with an install.htm page.  Click Next.  Select weather the application will be available both online and offline. Then click Finish. Once the initial deployment is completed, republish the solution this time mapping to the directory that holds the code that was just published.  This time the Publish Wizard contains and additional option.   The setup.exe file that is created has the install URL hardcoded in it.  It is this screen that allows you to specify the URL to use.  At some point a setup.exe file must be generated for production.  Enter the production URL and deploy the solution to the dev folder.  This file can then be saved for latter use in deployment to production.  During development this URL should be pointing to development site to avoid accidently installing the production application. Visual studio will publish the application to the desired location in the process it will create an anonymous ‘pfx’ certificate to sign the deployment configuration files.  A production certificate should be acquired in preparation for deployment to production.   Directory structure created by Visual Studio     Application files created by Visual Studio   Development web site (install.htm) created by Visual Studio Migrating Click Once Code to a new Server without using Visual Studio To migrate the Click Once application code to a new server, a tool called MageUI is needed to modify the .application and .manifest files.  The MageUI tool is usually located – ‘C:\Program Files\Microsoft SDKs\Windows\v6.0A\Bin’ folder or can be downloaded from the web. When deploying to a new environment copy all files in the project folder to the new server.  In this case the ‘ClickOnceSample’ folder and contents.  The old application versions can be deleted, in this case ‘ClickOnceSample_1_0_0_0’ and ‘ClickOnceSample_1_0_0_1’.  Open IIS Manager and create a virtual directory that points to the project folder.  Also make the publish.htm the default web page.   Run the ManeUI tool and then open the .application file in the root project folder (in this case in the ‘ClickOnceSample’ folder). Click on the Deployment Options in the left hand list and update the URL to the new server URL and save the changes.   When MageUI tries to save the file it will prompt for the file to be signed.   This step cannot be bypassed if you want the Click Once deployment to work from a web site.  The easiest solution to this for test is to use the auto generated certificate that Visual Studio created for the project.  This certificate can be found with the project source code.   To save time go to File>Preferences and configure the ‘Use default signing certificate’ fields.   Future deployments will only require application files to be transferred to the new server.  The only difference is then updating the .application file the ‘Version’ must be updated to match the new version and the ‘Application Reference’ has to be update to point to the new .manifest file.     Updating the Configuration File of a Click Once Deployment Package without using Visual Studio When an update to the configuration file is required, modifying the ClickOnceSample.exe.config.deploy file will not result in current users getting the new configurations.  We do not want to go back to Visual Studio and generate a new version as this might introduce unexpected code changes.  A new version of the application can be created by copying the folder (in this case ClickOnceSample_1_0_0_2) and pasting it into the application Files directory.  Rename the directory ‘ClickOnceSample_1_0_0_3’.  In the new folder open the configuration file in notepad and make the configuration changes. Run MageUI and open the manifest file in the newly copied directory (ClickOnceSample_1_0_0_3).   Edit the manifest version to reflect the newly copied files (in this case 1.0.0.3).  Then save the file.  Open the .application file in the root folder.  Again update the version to 1.0.0.3.  Since the file has not changed the Deployment Options/Start Location URL should still be correct.  The application Reference needs to be updated to point to the new versions .manifest file.  Save the file. Next time a user runs the application the new version of the configuration file will be down loaded.  It is worth noting that there are 2 different types of configuration parameter; application and user.  With Click Once deployment the difference is significant.  When an application is downloaded the configuration file is also brought down to the client machine.  The developer may have written code to update the user parameters in the application.  As a result each time a new version of the application is down loaded the user parameters are at risk of being overwritten.  With Click Once deployment the system knows if the user parameters are still the default values.  If they are they will be overwritten with the new default values in the configuration file.  If they have been updated by the user, they will not be overwritten. Settings configuration view in Visual Studio Production Deployment When deploying the code to production it is prudent to disable the development and test deployment sites.  This will allow errors such as incorrect URL to be quickly identified in the initial testing after deployment.  If the sites are active there is no way to know if the application was downloaded from the production deployment and not redirected to test or dev.   Troubleshooting Clicking the install button on the install.htm page fails. Error: URLDownloadToCacheFile failed with HRESULT '-2146697210' Error: An error occurred trying to download <file>   This is due to the setup.exe file pointing to the wrong location. ‘The setup.exe file that is created has the install URL hardcoded in it.  It is this screen that allows you to specify the URL to use.  At some point a setup.exe file must be generated for production.  Enter the production URL and deploy the solution to the dev folder.  This file can then be saved for latter use in deployment to production.  During development this URL should be pointing to development site to avoid accidently installing the production application.’

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  • Tools of the Trade

    - by Ajarn Mark Caldwell
    I got pretty excited a couple of days ago when my new laptop arrived. “The new phone books are here!  The new phone books are here!  I’m a somebody!” - Steve Martin in The Jerk It is a Dell Precision M4500 with an Intel i7 Core 2.8 GHZ running 64-bit Windows 7 with a 15.6” widescreen, 8 GB RAM, 256 GB SSD.  For some of you high fliers, this may be nothing to write home about, but compared to the 32–bit Windows XP laptop with 2 GB of RAM and a regular hard disk that I’m coming from, it’s a really nice step forward.  I won’t even bore you with the details of the desktop PC I was first given when I started here 5 1/2 years ago.  Let’s just say that things have improved.  One really nice thing is that while we are definitely running a lean and mean department in terms of staffing, my boss believes in supporting that lean staff with good tools in order to stay lean instead of having to spend even more money on additional employees.  Of course, that only goes so far, and at some point you have to add more people in order to get more work done, which is why we are bringing on-board a new employee and a new contract developer next week.  But that’s a different story for a different time. But the main topic for this post is to highlight the variety of tools that I use in my job and that you might find useful, too.  This is easy to do right now because the process of building up my new laptop from scratch has forced me to assemble a list of software that had to be installed and configured.  Keep in mind as you look through this list that I play many roles in our company.  My official title is Software Engineering Manager, but in addition to managing the team, I am also an active ASP.NET and SQL developer, the Database Administrator, and 50% of the SAN Administrator team.  So, without further ado, here are the tools and some comments about why I use them: Tool Purpose Virtual Clone Drive Easily mount an ISO image as a DVD Drive.  This is particularly handy when you are downloading disk images from Microsoft for your tools. SQL Server 2008 R2 Developer Edition We are migrating all of our active systems to SQL 2008 R2.  Developer Edition has all the features of Enterprise Edition, but intended for development use. SQL Server 2005 Developer Edition (BIDS ONLY) The migration to SSRS 2008 R2 is just getting started, and in the meantime, maintenance work still has to be done on the reports on our SQL 2005 server.  For some reason, you can’t use BIDS from 2008 to write reports for a 2005 server.  There is some different format and when you open 2005 reports in 2008 BIDS, it forces you to upgrade, and they can no longer be uploaded to a 2005 server.  Hopefully Microsoft will fix this soon in some manner similar to Visual Studio now allows you to pick which version of the .NET Framework you are coding against. Visual Studio 2010 Premium All of our application development is in ASP.NET, and we might as well use the tool designed for it. I’ve used a version of Visual Studio going all the way back to VB 6.0 and Visual Interdev. Vault Professional Client Several years ago we replaced Visual Source Safe with SourceGear Vault (then Fortress, and now Vault Pro), and I love it.  It is very reliable with low overhead - perfect for a small to medium size development team.  And being a small ISV, their support is exceptional. Red-Gate Developer Bundle with the SQL Source Control update for Vault I first used, and fell in love with, SQL Prompt shortly before Red-Gate bought it, and then Red-Gate’s first release made me love it even more.  SQL Refactor (which has since been rolled into the latest version of SQL Prompt) has saved me many hours and migraine’s trying to understand somebody else’s code when their indenting was nonexistant, or worse, irrational.  SQL Compare has been awesome for troubleshooting potential schema issues between different instances of system databases.  SQL Data Compare helped us identify the cause behind a bug which appeared in PROD but could not be reproduced in a nearly (but not quite exactly) identical copy in UAT.  And the newest tool we are embracing: SQL Source Control.  I blogged about it here (and here, and here) last December.  This is really going to help us keep each developer’s copy of the database in sync with one another. Fiddler Helps you watch the whole traffic stream on web visits.  Haven’t used it a lot, but it did help me track down some odd 404 errors we were finding in our own application logs.  Has some other JavaScript troubleshooting capabilities, but some of its usefulness has been supplanted by the Developer Tools option in IE8. Funduc Search & Replace Find any string anywhere in a mound of source code really, really fast.  Does RegEx searches, if you understand that foreign language.  Has really helped with some refactoring work to pinpoint, for example, everywhere a particular stored procedure is referenced, whether in .NET code or other SQL procedures (which we have in script files).  Provides in-context preview of the search results.  Fantastic tool, and a bargain price. SciTE SciTE is a Scintilla based Text Editor and it is a fantastic, light-weight tool for quickly reviewing (or writing) program code, SQL scripts, and extract files.  It has language-specific syntax highlighting.  I used it to write several batch and CMD programs a year ago, and to examine data extract files for exchanging information with other systems.  Extremely handy are the options to View End of Line and View Whitespace.  Ever receive a file that is supposed to use CRLF as an end-of-line marker, but really only has CRs?  SciTE will quickly make that visible. Infragistics Controls We do a lot of ASP.NET development, and frequently use the WebGrid, WebTab, and date picker controls.  We will likely be implementing the Hierarchical Data Grid soon.  Infragistics has control suites for WebForms, WinForms, Silverlight, and coming soon MVC/JQuery. WinZip - WITH Command-Line add-in The classic compression program with a great command-line interface that allows me to build those CMD (and soon PowerShell) programs for automated compression jobs.  Our versioned Build packages are zip files. XML Notepad Haven’t used this a lot myself, but one of my team really likes it for examining large XML files. LINQPad Again, haven’t used this one a lot, but it was recommended to me for learning and practicing my LINQ skills which will come in handy as we implement Entity Framework. SQL Sentry Plan Explorer SQL Server Show Plan on steroids.  Great for helping you focus on the parts of a large query that are of most importance.  Also great for just compressing the graphical plan into more readable layout. Araxis Merge A great DIFF and Merge tool.  SourceGear provides a great tool called DiffMerge that we use all the time, but occasionally, I like the cross-edit capabilities of Araxis Merge.  For a while, we also produced DIFF reports in HTML that showed all the changes that occurred between two releases.  This was most important when we were putting out very small, but very important hot fixes on a very politically hot system.  The reports produced by Araxis Merge gave the Director of IS assurance that we were not accidentally introducing ripples throughout the system with our releases. Idera SQL Admin Toolset A great collection of tools including a password checker to help analyze your SQL Server for weak user passwords, a Backup Status tool to quickly scan a large list of servers and databases to identify any that are overdue for backups.  Particularly helpful for highlighting new databases that have been deployed without getting included in your backup processing.  I also like Space Analyzer to keep an eye on disk space consumed by database files. Idera SQL Job Manager This free tool provides a nice calendar view of SQL Server Job Schedules, but to a degree, you also get what you pay for.  We will be purchasing SQL Sentry Event Manager later this year as an even better job schedule reviewer/manager.  But in the meantime, this at least gives me a good view on potential resource conflicts across multiple instances of SQL Server. DBFViewer 2000 I inherited a couple of FoxPro databases that I have to keep an eye on occasionally and have not yet been able to migrate them to SQL Server. Balsamiq Mockups We are still in evaluation-mode on this tool, but I really like it as a quick UI mockup tool that does not require Visual Studio, so someone other than a programmer can do UI design.  The interface looks hand-drawn which definitely has some psychological benefits when communicating to users, too. FeedDemon I have to stay on top of my WAY TOO MANY blog subscriptions somehow.  I may read blogs on a couple of different computers, and FeedDemon’s integration with Google Reader allows me to keep them all in sync.  I don’t particularly like the Google Reader interface, or the fact that it always wanted to mark articles as read just because I scrolled past them.  FeedDemon solves this problem for me, and provides a multi-tabbed interface which is good because fairly frequently one blog will link to something else I want to read, and I can end up with a half-dozen open tabs all from one article. Synergy+ In my office, I run four monitors across two computers all with one mouse and keyboard.  Synergy is the magic software that makes this work. TweetDeck I’m not the most active Tweeter in the world, but when I want to check-in with the Twitterverse, this really helps.  I have found the #sqlhelp and #PoshHelp hash tags particularly useful, and I also have columns setup to make it easy to monitor #sqlpass, #PASSProfDev, and short term events like #sqlsat68.   Whew!  That’s a lot.  No wonder it took me a couple of days to get everything setup the way I wanted it.  Oh, that and actually getting some work accomplished at the same time.  Anyway, I know that is a huge dump of info, and most people never make it here to the end, so for those who did, let me say, CONGRATULATIONS, you made it! I hope you’ll find a new tool or two to make your work life a little easier.

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  • LWJGL SlickUtil Texture Binding

    - by Matthew Dockerty
    I am making a 3D game using LWJGL and I have a texture class with static variables so that I only need to load textures once, even if I need to use them more than once. I am using Slick Util for this. When I bind a texture it works fine, but then when I try to render something else after I have rendered the model with the texture, the texture is still being bound. How do I unbind the texture and set the rendermode to the one that was in use before any textures were bound? Some of my code is below. The problem I am having is the player texture is being used in the box drawn around the player after it the model has been rendered. Model.java public class Model { public List<Vector3f> vertices = new ArrayList<Vector3f>(); public List<Vector3f> normals = new ArrayList<Vector3f>(); public ArrayList<Vector2f> textureCoords = new ArrayList<Vector2f>(); public List<Face> faces = new ArrayList<Face>(); public static Model TREE; public static Model PLAYER; public static void loadModels() { try { TREE = OBJLoader.loadModel(new File("assets/model/tree_pine_0.obj")); PLAYER = OBJLoader.loadModel(new File("assets/model/player.obj")); } catch (Exception e) { e.printStackTrace(); } } public void render(Vector3f position, Vector3f scale, Vector3f rotation, Texture texture, float shinyness) { glPushMatrix(); { texture.bind(); glColor3f(1, 1, 1); glTranslatef(position.x, position.y, position.z); glScalef(scale.x, scale.y, scale.z); glRotatef(rotation.x, 1, 0, 0); glRotatef(rotation.y, 0, 1, 0); glRotatef(rotation.z, 0, 0, 1); glMaterialf(GL_FRONT, GL_SHININESS, shinyness); glBegin(GL_TRIANGLES); { for (Face face : faces) { Vector2f t1 = textureCoords.get((int) face.textureCoords.x - 1); glTexCoord2f(t1.x, t1.y); Vector3f n1 = normals.get((int) face.normal.x - 1); glNormal3f(n1.x, n1.y, n1.z); Vector3f v1 = vertices.get((int) face.vertex.x - 1); glVertex3f(v1.x, v1.y, v1.z); Vector2f t2 = textureCoords.get((int) face.textureCoords.y - 1); glTexCoord2f(t2.x, t2.y); Vector3f n2 = normals.get((int) face.normal.y - 1); glNormal3f(n2.x, n2.y, n2.z); Vector3f v2 = vertices.get((int) face.vertex.y - 1); glVertex3f(v2.x, v2.y, v2.z); Vector2f t3 = textureCoords.get((int) face.textureCoords.z - 1); glTexCoord2f(t3.x, t3.y); Vector3f n3 = normals.get((int) face.normal.z - 1); glNormal3f(n3.x, n3.y, n3.z); Vector3f v3 = vertices.get((int) face.vertex.z - 1); glVertex3f(v3.x, v3.y, v3.z); } texture.release(); } glEnd(); } glPopMatrix(); } } Textures.java public class Textures { public static Texture FLOOR; public static Texture PLAYER; public static Texture SKYBOX_TOP; public static Texture SKYBOX_BOTTOM; public static Texture SKYBOX_FRONT; public static Texture SKYBOX_BACK; public static Texture SKYBOX_LEFT; public static Texture SKYBOX_RIGHT; public static void loadTextures() { try { FLOOR = TextureLoader.getTexture("PNG", new FileInputStream(new File("assets/model/floor.png"))); FLOOR.setTextureFilter(GL11.GL_NEAREST); PLAYER = TextureLoader.getTexture("PNG", new FileInputStream(new File("assets/model/tree_pine_0.png"))); PLAYER.setTextureFilter(GL11.GL_NEAREST); SKYBOX_TOP = TextureLoader.getTexture("PNG", new FileInputStream(new File("assets/textures/skybox_top.png"))); SKYBOX_TOP.setTextureFilter(GL11.GL_NEAREST); SKYBOX_BOTTOM = TextureLoader.getTexture("PNG", new FileInputStream(new File("assets/textures/skybox_bottom.png"))); SKYBOX_BOTTOM.setTextureFilter(GL11.GL_NEAREST); SKYBOX_FRONT = TextureLoader.getTexture("PNG", new FileInputStream(new File("assets/textures/skybox_front.png"))); SKYBOX_FRONT.setTextureFilter(GL11.GL_NEAREST); SKYBOX_BACK = TextureLoader.getTexture("PNG", new FileInputStream(new File("assets/textures/skybox_back.png"))); SKYBOX_BACK.setTextureFilter(GL11.GL_NEAREST); SKYBOX_LEFT = TextureLoader.getTexture("PNG", new FileInputStream(new File("assets/textures/skybox_left.png"))); SKYBOX_LEFT.setTextureFilter(GL11.GL_NEAREST); SKYBOX_RIGHT = TextureLoader.getTexture("PNG", new FileInputStream(new File("assets/textures/skybox_right.png"))); SKYBOX_RIGHT.setTextureFilter(GL11.GL_NEAREST); } catch (Exception e) { e.printStackTrace(); } } } Player.java public class Player { private Vector3f position; private float yaw; private float moveSpeed; public Player(float x, float y, float z, float yaw, float moveSpeed) { this.position = new Vector3f(x, y, z); this.yaw = yaw; this.moveSpeed = moveSpeed; } public void update() { if (Keyboard.isKeyDown(Keyboard.KEY_W)) walkForward(moveSpeed); if (Keyboard.isKeyDown(Keyboard.KEY_S)) walkBackwards(moveSpeed); if (Keyboard.isKeyDown(Keyboard.KEY_A)) strafeLeft(moveSpeed); if (Keyboard.isKeyDown(Keyboard.KEY_D)) strafeRight(moveSpeed); if (Mouse.isButtonDown(0)) yaw += Mouse.getDX(); LowPolyRPG.getInstance().getCamera().setPosition(-position.x, -position.y, -position.z); LowPolyRPG.getInstance().getCamera().setYaw(yaw); } public void walkForward(float distance) { position.setX(position.getX() + distance * (float) Math.sin(Math.toRadians(yaw))); position.setZ(position.getZ() - distance * (float) Math.cos(Math.toRadians(yaw))); } public void walkBackwards(float distance) { position.setX(position.getX() - distance * (float) Math.sin(Math.toRadians(yaw))); position.setZ(position.getZ() + distance * (float) Math.cos(Math.toRadians(yaw))); } public void strafeLeft(float distance) { position.setX(position.getX() + distance * (float) Math.sin(Math.toRadians(yaw - 90))); position.setZ(position.getZ() - distance * (float) Math.cos(Math.toRadians(yaw - 90))); } public void strafeRight(float distance) { position.setX(position.getX() + distance * (float) Math.sin(Math.toRadians(yaw + 90))); position.setZ(position.getZ() - distance * (float) Math.cos(Math.toRadians(yaw + 90))); } public void render() { Model.PLAYER.render(new Vector3f(position.x, position.y + 12, position.z), new Vector3f(3, 3, 3), new Vector3f(0, -yaw + 90, 0), Textures.PLAYER, 128); GL11.glPushMatrix(); GL11.glTranslatef(position.getX(), position.getY(), position.getZ()); GL11.glRotatef(-yaw, 0, 1, 0); GL11.glScalef(5.8f, 21, 2.2f); GL11.glDisable(GL11.GL_LIGHTING); GL11.glLineWidth(3); GL11.glBegin(GL11.GL_LINE_STRIP); GL11.glColor3f(1, 1, 1); glVertex3f(1f, 0f, -1f); glVertex3f(-1f, 0f, -1f); glVertex3f(-1f, 1f, -1f); glVertex3f(1f, 1f, -1f); glVertex3f(-1f, 0f, 1f); glVertex3f(1f, 0f, 1f); glVertex3f(1f, 1f, 1f); glVertex3f(-1f, 1f, 1f); glVertex3f(1f, 1f, -1f); glVertex3f(-1f, 1f, -1f); glVertex3f(-1f, 1f, 1f); glVertex3f(1f, 1f, 1f); glVertex3f(1f, 0f, 1f); glVertex3f(-1f, 0f, 1f); glVertex3f(-1f, 0f, -1f); glVertex3f(1f, 0f, -1f); glVertex3f(1f, 0f, 1f); glVertex3f(1f, 0f, -1f); glVertex3f(1f, 1f, -1f); glVertex3f(1f, 1f, 1f); glVertex3f(-1f, 0f, -1f); glVertex3f(-1f, 0f, 1f); glVertex3f(-1f, 1f, 1f); glVertex3f(-1f, 1f, -1f); GL11.glEnd(); GL11.glEnable(GL11.GL_LIGHTING); GL11.glPopMatrix(); } public Vector3f getPosition() { return new Vector3f(-position.x, -position.y, -position.z); } public float getX() { return position.getX(); } public float getY() { return position.getY(); } public float getZ() { return position.getZ(); } public void setPosition(Vector3f position) { this.position = position; } public void setPosition(float x, float y, float z) { this.position.setX(x); this.position.setY(y); this.position.setZ(z); } } Thanks for the help.

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  • Do you play Sudoku ?

    - by Gilles Haro
    Did you know that 11gR2 database could solve a Sudoku puzzle with a single query and, most of the time, and this in less than a second ? The following query shows you how ! Simply pass a flattened Sudoku grid to it a get the result instantaneously ! col "Solution" format a9 col "Problem" format a9 with Iteration( initialSudoku, Step, EmptyPosition ) as ( select initialSudoku, InitialSudoku, instr( InitialSudoku, '-' )        from ( select '--64----2--7-35--1--58-----27---3--4---------4--2---96-----27--7--58-6--3----18--' InitialSudoku from dual )    union all    select initialSudoku        , substr( Step, 1, EmptyPosition - 1 ) || OneDigit || substr( Step, EmptyPosition + 1 )         , instr( Step, '-', EmptyPosition + 1 )      from Iteration         , ( select to_char( rownum ) OneDigit from dual connect by rownum <= 9 ) OneDigit     where EmptyPosition > 0       and not exists          ( select null              from ( select rownum IsPossible from dual connect by rownum <= 9 )             where OneDigit = substr( Step, trunc( ( EmptyPosition - 1 ) / 9 ) * 9 + IsPossible, 1 )   -- One line must contain the 1-9 digits                or OneDigit = substr( Step, mod( EmptyPosition - 1, 9 ) - 8 + IsPossible * 9, 1 )      -- One row must contain the 1-9 digits                or OneDigit = substr( Step, mod( trunc( ( EmptyPosition - 1 ) / 3 ), 3 ) * 3           -- One square must contain the 1-9 digits                            + trunc( ( EmptyPosition - 1 ) / 27 ) * 27 + IsPossible                            + trunc( ( IsPossible - 1 ) / 3 ) * 6 , 1 )          ) ) select initialSudoku "Problem", Step "Solution"    from Iteration  where EmptyPosition = 0 ;   The Magic thing behind this is called Recursive Subquery Factoring. The Oracle documentation gives the following definition: If a subquery_factoring_clause refers to its own query_name in the subquery that defines it, then the subquery_factoring_clause is said to be recursive. A recursive subquery_factoring_clause must contain two query blocks: the first is the anchor member and the second is the recursive member. The anchor member must appear before the recursive member, and it cannot reference query_name. The anchor member can be composed of one or more query blocks combined by the set operators: UNION ALL, UNION, INTERSECT or MINUS. The recursive member must follow the anchor member and must reference query_name exactly once. You must combine the recursive member with the anchor member using the UNION ALL set operator. This new feature is a replacement of this old Hierarchical Query feature that exists in Oracle since the days of Aladdin (well, at least, release 2 of the database in 1977). Everyone remembers the old syntax : select empno, ename, job, mgr, level      from   emp      start with mgr is null      connect by prior empno = mgr; that could/should be rewritten (but not as often as it should) as withT_Emp (empno, name, level) as        ( select empno, ename, job, mgr, level             from   emp             start with mgr is null             connect by prior empno = mgr        ) select * from   T_Emp; which uses the "with" syntax, whose main advantage is to clarify the readability of the query. Although very efficient, this syntax had the disadvantage of being a Non-Ansi Sql Syntax. Ansi-Sql version of Hierarchical Query is called Recursive Subquery Factoring. As of 11gR2, Oracle got compliant with Ansi Sql and introduced Recursive Subquery Factoring. It is basically an extension of the "With" clause that enables recursion. Now, the new syntax for the query would be with T_Emp (empno, name, job, mgr, hierlevel) as       ( select E.empno, E.ename, E.job, E.mgr, 1 from emp E where E.mgr is null         union all         select E.empno, E.ename, E.job, E.mgr, T.hierlevel + 1from emp E                                                                                                            join T_Emp T on ( E.mgr = T.empno ) ) select * from   T_Emp; The anchor member is a replacement for the "start with" The recursive member is processed through iterations. It joins the Source table (EMP) with the result from the Recursive Query itself (T_Emp) Each iteration works with the results of all its preceding iterations.     Iteration 1 works on the results of the first query     Iteration 2 works on the results of Iteration 1 and first query     Iteration 3 works on the results of Iteration 1, Iteration 2 and first query. So, knowing that, the Sudoku query it self-explaining; The anchor member contains the "Problem" : The Initial Sudoku and the Position of the first "hole" in the grid. The recursive member tries to replace the considered hole with any of the 9 digit that would satisfy the 3 rules of sudoku Recursion progress through the grid until it is complete.   Another example :  Fibonaccy Numbers :  un = (un-1) + (un-2) with Fib (u1, u2, depth) as   (select 1, 1, 1 from dual    union all    select u1+u2, u1, depth+1 from Fib where depth<10) select u1 from Fib; Conclusion Oracle brings here a new feature (which, to be honest, already existed on other concurrent systems) and extends the power of the database to new boundaries. It’s now up to developers to try and test it and find more useful application than solving puzzles… But still, solving a Sudoku in less time it takes to say it remains impressive… Interesting links: You might be interested by the following links which cover different aspects of this feature Oracle Documentation Lucas Jellema 's Blog Fibonaci Numbers

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  • Performance Enhancement in Full-Text Search Query

    - by Calvin Sun
    Ever since its first release, we are continuing consolidating and developing InnoDB Full-Text Search feature. There is one recent improvement that worth blogging about. It is an effort with MySQL Optimizer team that simplifies some common queries’ Query Plans and dramatically shorted the query time. I will describe the issue, our solution and the end result by some performance numbers to demonstrate our efforts in continuing enhancement the Full-Text Search capability. The Issue: As we had discussed in previous Blogs, InnoDB implements Full-Text index as reversed auxiliary tables. The query once parsed will be reinterpreted into several queries into related auxiliary tables and then results are merged and consolidated to come up with the final result. So at the end of the query, we’ll have all matching records on hand, sorted by their ranking or by their Doc IDs. Unfortunately, MySQL’s optimizer and query processing had been initially designed for MyISAM Full-Text index, and sometimes did not fully utilize the complete result package from InnoDB. Here are a couple examples: Case 1: Query result ordered by Rank with only top N results: mysql> SELECT FTS_DOC_ID, MATCH (title, body) AGAINST ('database') AS SCORE FROM articles ORDER BY score DESC LIMIT 1; In this query, user tries to retrieve a single record with highest ranking. It should have a quick answer once we have all the matching documents on hand, especially if there are ranked. However, before this change, MySQL would almost retrieve rankings for almost every row in the table, sort them and them come with the top rank result. This whole retrieve and sort is quite unnecessary given the InnoDB already have the answer. In a real life case, user could have millions of rows, so in the old scheme, it would retrieve millions of rows' ranking and sort them, even if our FTS already found there are two 3 matched rows. Apparently, the million ranking retrieve is done in vain. In above case, it should just ask for 3 matched rows' ranking, all other rows' ranking are 0. If it want the top ranking, then it can just get the first record from our already sorted result. Case 2: Select Count(*) on matching records: mysql> SELECT COUNT(*) FROM articles WHERE MATCH (title,body) AGAINST ('database' IN NATURAL LANGUAGE MODE); In this case, InnoDB search can find matching rows quickly and will have all matching rows. However, before our change, in the old scheme, every row in the table was requested by MySQL one by one, just to check whether its ranking is larger than 0, and later comes up a count. In fact, there is no need for MySQL to fetch all rows, instead InnoDB already had all the matching records. The only thing need is to call an InnoDB API to retrieve the count The difference can be huge. Following query output shows how big the difference can be: mysql> select count(*) from searchindex_inno where match(si_title, si_text) against ('people')  +----------+ | count(*) | +----------+ | 666877 | +----------+ 1 row in set (16 min 17.37 sec) So the query took almost 16 minutes. Let’s see how long the InnoDB can come up the result. In InnoDB, you can obtain extra diagnostic printout by turning on “innodb_ft_enable_diag_print”, this will print out extra query info: Error log: keynr=2, 'people' NL search Total docs: 10954826 Total words: 0 UNION: Searching: 'people' Processing time: 2 secs: row(s) 666877: error: 10 ft_init() ft_init_ext() keynr=2, 'people' NL search Total docs: 10954826 Total words: 0 UNION: Searching: 'people' Processing time: 3 secs: row(s) 666877: error: 10 Output shows it only took InnoDB only 3 seconds to get the result, while the whole query took 16 minutes to finish. So large amount of time has been wasted on the un-needed row fetching. The Solution: The solution is obvious. MySQL can skip some of its steps, optimize its plan and obtain useful information directly from InnoDB. Some of savings from doing this include: 1) Avoid redundant sorting. Since InnoDB already sorted the result according to ranking. MySQL Query Processing layer does not need to sort to get top matching results. 2) Avoid row by row fetching to get the matching count. InnoDB provides all the matching records. All those not in the result list should all have ranking of 0, and no need to be retrieved. And InnoDB has a count of total matching records on hand. No need to recount. 3) Covered index scan. InnoDB results always contains the matching records' Document ID and their ranking. So if only the Document ID and ranking is needed, there is no need to go to user table to fetch the record itself. 4) Narrow the search result early, reduce the user table access. If the user wants to get top N matching records, we do not need to fetch all matching records from user table. We should be able to first select TOP N matching DOC IDs, and then only fetch corresponding records with these Doc IDs. Performance Results and comparison with MyISAM The result by this change is very obvious. I includes six testing result performed by Alexander Rubin just to demonstrate how fast the InnoDB query now becomes when comparing MyISAM Full-Text Search. These tests are base on the English Wikipedia data of 5.4 Million rows and approximately 16G table. The test was performed on a machine with 1 CPU Dual Core, SSD drive, 8G of RAM and InnoDB_buffer_pool is set to 8 GB. Table 1: SELECT with LIMIT CLAUSE mysql> SELECT si_title, match(si_title, si_text) against('family') as rel FROM si WHERE match(si_title, si_text) against('family') ORDER BY rel desc LIMIT 10; InnoDB MyISAM Times Faster Time for the query 1.63 sec 3 min 26.31 sec 127 You can see for this particular query (retrieve top 10 records), InnoDB Full-Text Search is now approximately 127 times faster than MyISAM. Table 2: SELECT COUNT QUERY mysql>select count(*) from si where match(si_title, si_text) against('family‘); +----------+ | count(*) | +----------+ | 293955 | +----------+ InnoDB MyISAM Times Faster Time for the query 1.35 sec 28 min 59.59 sec 1289 In this particular case, where there are 293k matching results, InnoDB took only 1.35 second to get all of them, while take MyISAM almost half an hour, that is about 1289 times faster!. Table 3: SELECT ID with ORDER BY and LIMIT CLAUSE for selected terms mysql> SELECT <ID>, match(si_title, si_text) against(<TERM>) as rel FROM si_<TB> WHERE match(si_title, si_text) against (<TERM>) ORDER BY rel desc LIMIT 10; Term InnoDB (time to execute) MyISAM(time to execute) Times Faster family 0.5 sec 5.05 sec 10.1 family film 0.95 sec 25.39 sec 26.7 Pizza restaurant orange county California 0.93 sec 32.03 sec 34.4 President united states of America 2.5 sec 36.98 sec 14.8 Table 4: SELECT title and text with ORDER BY and LIMIT CLAUSE for selected terms mysql> SELECT <ID>, si_title, si_text, ... as rel FROM si_<TB> WHERE match(si_title, si_text) against (<TERM>) ORDER BY rel desc LIMIT 10; Term InnoDB (time to execute) MyISAM(time to execute) Times Faster family 0.61 sec 41.65 sec 68.3 family film 1.15 sec 47.17 sec 41.0 Pizza restaurant orange county california 1.03 sec 48.2 sec 46.8 President united states of america 2.49 sec 44.61 sec 17.9 Table 5: SELECT ID with ORDER BY and LIMIT CLAUSE for selected terms mysql> SELECT <ID>, match(si_title, si_text) against(<TERM>) as rel  FROM si_<TB> WHERE match(si_title, si_text) against (<TERM>) ORDER BY rel desc LIMIT 10; Term InnoDB (time to execute) MyISAM(time to execute) Times Faster family 0.5 sec 5.05 sec 10.1 family film 0.95 sec 25.39 sec 26.7 Pizza restaurant orange county califormia 0.93 sec 32.03 sec 34.4 President united states of america 2.5 sec 36.98 sec 14.8 Table 6: SELECT COUNT(*) mysql> SELECT count(*) FROM si_<TB> WHERE match(si_title, si_text) against (<TERM>) LIMIT 10; Term InnoDB (time to execute) MyISAM(time to execute) Times Faster family 0.47 sec 82 sec 174.5 family film 0.83 sec 131 sec 157.8 Pizza restaurant orange county califormia 0.74 sec 106 sec 143.2 President united states of america 1.96 sec 220 sec 112.2  Again, table 3 to table 6 all showing InnoDB consistently outperform MyISAM in these queries by a large margin. It becomes obvious the InnoDB has great advantage over MyISAM in handling large data search. Summary: These results demonstrate the great performance we could achieve by making MySQL optimizer and InnoDB Full-Text Search more tightly coupled. I think there are still many cases that InnoDB’s result info have not been fully taken advantage of, which means we still have great room to improve. And we will continuously explore the area, and get more dramatic results for InnoDB full-text searches. Jimmy Yang, September 29, 2012

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  • Enabling XML-documentation for code contracts

    - by DigiMortal
    One nice feature that code contracts offer is updating of code documentation. If you are using source code documenting features of Visual Studio then code contracts may automate some tasks you otherwise have to implement manually. In this posting I will show you some XML documentation files with documented contracts. I will also explain how this feature works. Enabling XML-documentation in project settings As a first thing let’s enable generating of code documentation under project settings. Open project properties, move to Build page and make check to checkbox called “XML documentation file”. Save project settings and rebuild project. When project is built go to bin/Debug folder and open the XML-file. Here is my XML. <?xml version="1.0"?> <doc>     <assembly>         <name>Eneta.Examples.CodeContracts.Testable</name>     </assembly>     <members>         <member name="T:Eneta.Examples.CodeContracts.Testable.Randomizer">             <summary>             Class for generating random integers in user specified range.             </summary>         </member>         <member name="M:Eneta.Examples.CodeContracts.Testable.Randomizer.#ctor(Eneta.Examples.CodeContracts.Testable.IRandomGenerator)">             <summary>             Constructor of Randomizer. Initializes Randomizer class.             </summary>             <param name="generator">Instance of random number generator.</param>         </member>         <member name="M:Eneta.Examples.CodeContracts.Testable.Randomizer.GetRandomFromRangeContracted(System.Int32,System.Int32)">             <summary>             Returns random integer in given range.             </summary>             <param name="min">Minimum value of random integer.</param>             <param name="max">Maximum value of random integer.</param>         </member>     </members> </doc> You can see nothing about code contracts here. Enabling code contracts documentation Code contracts have their own settings and conditions for documentation. Open project properties and move to Code Contracts tab. From “Contract Reference Assembly” dropdown check Build and make check to checkbox “Emit contracts into XML doc file”. And again – save project setting, build the project and move to bin/Debug folder. Now you can see that there are two files for XML-documentation: <assembly name>.XML <assembly name>.old.XML First files is documentation with contracts, second file is original documentation without contracts. Let’s see now what is inside our new XML-documentation file. <?xml version="1.0"?> <doc>   <assembly>     <name>Eneta.Examples.CodeContracts.Testable</name>   </assembly>   <members>     <member name="T:Eneta.Examples.CodeContracts.Testable.Randomizer">       <summary>             Class for generating random integers in user specified range.             </summary>     </member>     <member name="M:Eneta.Examples.CodeContracts.Testable.Randomizer.#ctor(Eneta.Examples.CodeContracts.Testable.IRandomGenerator)">       <summary>             Constructor of Randomizer. Initializes Randomizer class.             </summary>       <param name="generator">Instance of random number generator.</param>     </member>     <member name="M:Eneta.Examples.CodeContracts.Testable.Randomizer.GetRandomFromRangeContracted(System.Int32,System.Int32)">       <summary>             Returns random integer in given range.             </summary>       <param name="min">Minimum value of random integer.</param>       <param name="max">Maximum value of random integer.</param>       <requires description="Min must be less than max" exception="T:System.ArgumentOutOfRangeException">                 min &lt; max</requires>       <exception cref="T:System.ArgumentOutOfRangeException">                 min &gt;= max</exception>       <ensures description="Return value is out of range">                 Contract.Result&lt;int&gt;() &gt;= min &amp;&amp;                 Contract.Result&lt;int&gt;() &lt;= max</ensures>     </member>   </members> </doc> As you can see then code contracts are pretty well documented. Messages that I provided with code contracts are also available in documentation. If I wrote very good and informative messages then these messages are very useful also in contracts documentation. Code contracts and Sandcastle Sandcastle knows nothing about code contracts by default. There is separate package of file for Sandcastle that is provided you by code contracts installation. You can read from code contracts manual: “Sandcastle (http://www.codeplex.com/Sandcastle) is a freely available tool that generates help les and web sites describing your APIs, based on the XML doc comments in your source code. The CodeContracts install contains a set of les that can be copied over a Sandcastle installation to take advantage of the additional contract information. The produced documentation adds a contract section to methods with declared requires and/or ensures. In order for Sandcastle to produce Contract sections, you need to patch a number of files in its installation. Please refer to the Sandcastle Readme.txt found under Start Menu/CodeContracts/Sandcastle for instructions. A future release of Sandcastle will hopefully support contract sections without the need for this patching step.” Integrating code contracts documentation to Sandcastle will be one of my next postings about code contracts. Conclusion if you are using code documentation then documentation about code contracts can be added to documentation very easily. All you have to do is to enable XML-documentation for contracts and build your project. Later you can use Sandcastle files provided by code contracts installer to integrate contracts documentation to your output documentation package.

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  • Issue 15: Oracle Exadata Marketing Campaigns

    - by rituchhibber
         PARTNER FOCUS Oracle ExadataMarketing Campaign Steve McNickleVP Europe, cVidya Steve McNickle is VP Europe for cVidya, an innovative provider of revenue intelligence solutions for telecom, media and entertainment service providers including AT&T, BT, Deutsche Telecom and Vodafone. The company's product portfolio helps operators and service providers maximise margins, improve customer experience and optimise ecosystem relationships through revenue assurance, fraud and security management, sales performance management, pricing analytics, and inter-carrier services. cVidya has partnered with Oracle for more than a decade. RESOURCES -- Oracle PartnerNetwork (OPN) Oracle Exastack Program Oracle Exastack Optimized Oracle Exastack Labs and Enablement Resources Oracle Engineered Systems Oracle Communications cVidya SUBSCRIBE FEEDBACK PREVIOUS ISSUES Are you ready for Oracle OpenWorld this October? -- -- Please could you tell us a little about cVidya's partnering history with Oracle, and expand on your Oracle Exastack accreditations? "cVidya was established just over ten years ago and we've had a strong relationship with Oracle almost since the very beginning. Through our Revenue Intelligence work with some of the world's largest service providers we collect tremendous amounts of information, amounting to billions of records per day. We help our clients to collect, store and analyse that data to ensure that their end customers are getting the best levels of service, are billed correctly, and are happy that they are on the correct price plan. We have been an Oracle Gold level partner for seven years, and crucially just two months ago we were also accredited as Oracle Exastack Optimized for MoneyMap, our core Revenue Assurance solution. Very soon we also expect to be Oracle Exastack Optimized DRMap, our Data Retention solution." What unique capabilities and customer benefits does Oracle Exastack add to your applications? "Oracle Exastack enables us to deliver radical benefits to our customers. A typical mobile operator in the UK might handle between 500 million and two billion call data record details daily. Each transaction needs to be validated, billed correctly and fraud checked. Because of the enormous volumes involved, our clients demand scalable infrastructure that allows them to efficiently acquire, store and process all that data within controlled cost, space and environmental constraints. We have proved that the Oracle Exadata system can process data up to seven times faster and load it as much as 20 times faster than other standard best-of-breed server approaches. With the Oracle Exadata Database Machine they can reduce their datacentre equipment from say, the six or seven cabinets that they needed in the past, down to just one. This dramatic simplification delivers incredible value to the customer by cutting down enormously on all of their significant cost, space, energy, cooling and maintenance overheads." "The Oracle Exastack Program has given our clients the ability to switch their focus from reactive to proactive. Traditionally they may have spent 80 percent of their day processing, and just 20 percent enabling end customers to see advanced analytics, and avoiding issues before they occur. With our solutions and Oracle Exadata they can now switch that balance around entirely, resulting not only in reduced revenue leakage, but a far higher focus on proactive leakage prevention. How has the Oracle Exastack Program transformed your customer business? "We can already see the impact. Oracle solutions allow our delivery teams to achieve successful deployments, happy customers and self-satisfaction, and the power of Oracle's Exa solutions is easy to measure in terms of their transformational ability. We gained our first sale into a major European telco by demonstrating the major performance gains that would transform their business. Clients can measure the ease of organisational change, the early prevention of business issues, the reduction in manpower required to provide protection and coverage across all their products and services, plus of course end customer satisfaction. If customers know that that service is provided accurately and that their bills are calculated correctly, then over time this satisfaction can be attributed to revenue intelligence and the underlying systems which provide it. Combine this with the further integration we have with the other layers of the Oracle stack, including the telecommunications offerings such as NCC, OCDM and BRM, and the result is even greater customer value—not to mention the increased speed to market and the reduced project risk." What does the Oracle Exastack community bring to cVidya, both in terms of general benefits, and also tangible new opportunities and partnerships? "A great deal. We have participated in the Oracle Exastack community heavily over the past year, and have had lots of meetings with Oracle and our peers around the globe. It brings us into contact with like-minded, innovative partners, who like us are not happy to just stand still and want to take fresh technology to their customer base in order to gain enhanced value. We identified three new partnerships in each of two recent meetings, and hope these will open up new opportunities, not only in areas that exactly match where we operate today, but also in some new associative areas that will expand our reach into new business sectors. Notably, thanks to the Exastack community we were invited on stage at last year's Oracle OpenWorld conference. Appearing so publically with Oracle senior VP Judson Althoff elevated awareness and visibility of cVidya and has enabled us to participate in a number of other events with Oracle over the past eight months. We've been involved in speaking opportunities, forums and exhibitions, providing us with invaluable opportunities that we wouldn't otherwise have got close to." How has Exastack differentiated cVidya as an ISV, and helped you to evolve your business to the next level? "When we are selling to our core customer base of Tier 1 telecommunications providers, we know that they want more than just software. They want an enduring partnership that will last many years, they want innovation, and a forward thinking partner who knows how to guide them on where they need to be to meet market demand three, five or seven years down the line. Membership of respected global bodies, such as the Telemanagement Forum enables us to lead standard adherence in our area of business, giving us a lot of credibility, but Oracle is also involved in this forum with its own telecommunications portfolio, strengthening our position still further. When we approach CEOs, CTOs and CIOs at the very largest Tier 1 operators, not only can we easily show them that our technology is fantastic, we can also talk about our strong partnership with Oracle, and our joint embracing of today's standards and tomorrow's innovation." Where would you like cVidya to be in one year's time? "We want to get all of our relevant products Oracle Exastack Optimized. Our MoneyMap Revenue Assurance solution is already Exastack Optimised, our DRMAP Data Retention Solution should be Exastack Optimised within the next month, and our FraudView Fraud Management solution within the next two to three months. We'd then like to extend our Oracle accreditation out to include other members of the Oracle Engineered Systems family. We are moving into the 'Big Data' space, and so we're obviously very keen to work closely with Oracle to conduct pilots, map new technologies onto Oracle Big Data platforms, and embrace and measure the benefits of other Oracle systems, namely Oracle Exalogic Elastic Cloud, the Oracle Exalytics In-Memory Machine and the Oracle SPARC SuperCluster. We would also like to examine how the Oracle Database Appliance might benefit our Tier 2 service provider customers. Finally, we'd also like to continue working with the Oracle Communications Global Business Unit (CGBU), furthering our integration with Oracle billing products so that we are able to quickly deploy fraud solutions into Oracle's Engineered System stack, give operational benefits to our clients that are pre-integrated, more cost-effective, and can be rapidly deployed rapidly and producing benefits in three months, not nine months." Chris Baker ,Senior Vice President, Oracle Worldwide ISV-OEM-Java Sales Chris Baker is the Global Head of ISV/OEM Sales responsible for working with ISV/OEM partners to maximise Oracle's business through those partners, whilst maximising those partners' business to their end users. Chris works with partners, customers, innovators, investors and employees to develop innovative business solutions using Oracle products, services and skills. Firstly, could you please explain Oracle's current strategy for ISV partners, globally and in EMEA? "Oracle customers use independent software vendor (ISV) applications to run their businesses. They use them to generate revenue and to fulfil obligations to their own customers. Our strategy is very straight-forward. We want all of our ISV partners and OEMs to concentrate on the things that they do the best – building applications to meet the unique industry and functional requirements of their customer. We want to ensure that we deliver a best in class application platform so the ISV is free to concentrate their effort on their application functionality and user experience We invest over four billion dollars in research and development every year, and we want our ISVs to benefit from all of that investment in operating systems, virtualisation, databases, middleware, engineered systems, and other hardware. By doing this, we help them to reduce their costs, gain more consistency and agility for quicker implementations, and also rapidly differentiate themselves from other application vendors. It's all about simplification because we believe that around 25 to 30 percent of the development costs incurred by many ISVs are caused by customising infrastructure and have nothing to do with their applications. Our strategy is to enable our ISV partners to standardise their application platform using engineered architecture, so they can write once to the Oracle stack and deploy seamlessly in the cloud, on-premise, or in hybrid deployments. It's really important that architecture is the same in order to keep cost and time overheads at a minimum, so we provide standardisation and an environment that enables our ISVs to concentrate on the core business that makes them the most money and brings them success." How do you believe this strategy is helping the ISVs to work hand-in-hand with Oracle to ensure that end customers get the industry-leading solutions that they need? "We work with our ISVs not just to help them be successful, but also to help them market themselves. We have something called the 'Oracle Exastack Ready Program', which enables ISVs to publicise themselves as 'Ready' to run the core software platforms that run on Oracle's engineered systems including Exadata and Exalogic. So, for example, they can become 'Database Ready' which means that they use the latest version of Oracle Database and therefore can run their application without modification on Exadata or the Oracle Database Appliance. Alternatively, they can become WebLogic Ready, Oracle Linux Ready and Oracle Solaris Ready which means they run on the latest release and therefore can run their application, with no new porting work, on Oracle Exalogic. Those 'Ready' logos are important in helping ISVs advertise to their customers that they are using the latest technologies which have been fully tested. We now also have Exadata Ready and Exalogic Ready programmes which allow ISVs to promote the certification of their applications on these platforms. This highlights these partners to Oracle customers as having solutions that run fluently on the Oracle Exadata Database Machine, the Oracle Exalogic Elastic Cloud or one of our other engineered systems. This makes it easy for customers to identify solutions and provides ISVs with an avenue to connect with Oracle customers who are rapidly adopting engineered systems. We have also taken this programme to the next level in the shape of 'Oracle Exastack Optimized' for partners whose applications run best on the Oracle stack and have invested the time to fully optimise application performance. We ensure that Exastack Optimized partner status is promoted and supported by press releases, and we help our ISVs go to market and differentiate themselves through the use our technology and the standardisation it delivers. To date we have had several hundred organisations successfully work through our Exastack Optimized programme." How does Oracle's strategy of offering pre-integrated open platform software and hardware allow ISVs to bring their products to market more quickly? "One of the problems for many ISVs is that they have to think very carefully about the technology on which their solutions will be deployed, particularly in the cloud or hosted environments. They have to think hard about how they secure these environments, whether the concern is, for example, middleware, identity management, or securing personal data. If they don't use the technology that we build-in to our products to help them to fulfil these roles, they then have to build it themselves. This takes time, requires testing, and must be maintained. By taking advantage of our technology, partners will now know that they have a standard platform. They will know that they can confidently talk about implementation being the same every time they do it. Very large ISV applications could once take a year or two to be implemented at an on-premise environment. But it wasn't just the configuration of the application that took the time, it was actually the infrastructure - the different hardware configurations, operating systems and configurations of databases and middleware. Now we strongly believe that it's all about standardisation and repeatability. It's about making sure that our partners can do it once and are then able to roll it out many different times using standard componentry." What actions would you recommend for existing ISV partners that are looking to do more business with Oracle and its customer base, not only to maximise benefits, but also to maximise partner relationships? "My team, around the world and in the EMEA region, is available and ready to talk to any of our ISVs and to explore the possibilities together. We run programmes like 'Excite' and 'Insight' to help us to understand how we can help ISVs with architecture and widen their environments. But we also want to work with, and look at, new opportunities - for example, the Machine-to-Machine (M2M) market or 'The Internet of Things'. Over the next few years, many millions, indeed billions of devices will be collecting massive amounts of data and communicating it back to the central systems where ISVs will be running their applications. The only way that our partners will be able to provide a single vendor 'end-to-end' solution is to use Oracle integrated systems at the back end and Java on the 'smart' devices collecting the data – a complete solution from device to data centre. So there are huge opportunities to work closely with our ISVs, using Oracle's complete M2M platform, to provide the infrastructure that enables them to extract maximum value from the data collected. If any partners don't know where to start or who to contact, then they can contact me directly at [email protected] or indeed any of our teams across the EMEA region. We want to work with ISVs to help them to be as successful as they possibly can through simplification and speed to market, and we also want all of the top ISVs in the world based on Oracle." What opportunities are immediately opened to new ISV partners joining the OPN? "As you know OPN is very, very important. New members will discover a huge amount of content that instantly becomes accessible to them. They can access a wealth of no-cost training and enablement materials to build their expertise in Oracle technology. They can download Oracle software and use it for development projects. They can help themselves become more competent by becoming part of a true community and uncovering new opportunities by working with Oracle and their peers in the Oracle Partner Network. As well as publishing massive amounts of information on OPN, we also hold our global Oracle OpenWorld event, at which partners play a huge role. This takes place at the end of September and the beginning of October in San Francisco. Attending ISV partners have an unrivalled opportunity to contribute to elements such as the OpenWorld / OPN Exchange, at which they can talk to other partners and really begin thinking about how they can move their businesses on and play key roles in a very large ecosystem which revolves around technology and standardisation." Finally, are there any other messages that you would like to share with the Oracle ISV community? "The crucial message that I always like to reinforce is architecture, architecture and architecture! The key opportunities that ISVs have today revolve around standardising their architectures so that they can confidently think: “I will I be able to do exactly the same thing whenever a customer is looking to deploy on-premise, hosted or in the cloud”. The right architecture is critical to being competitive and to really start changing the game. We want to help our ISV partners to do just that; to establish standard architecture and to seize the opportunities it opens up for them. New market opportunities like M2M are enormous - just look at how many devices are all around you right now. We can help our partners to interface with these devices more effectively while thinking about their entire ecosystem, rather than just the piece that they have traditionally focused upon. With standardised architecture, we can help people dramatically improve their speed, reach, agility and delivery of enhanced customer satisfaction and value all the way from the Java side to their centralised systems. All Oracle ISV partners must take advantage of these opportunities, which is why Oracle will continue to invest in and support them." -- Gergely Strbik is Oracle Hardware and Software Product Manager for Avnet in Hungary. Avnet Technology Solutions is an OracleValue Added Distributor focused on the development of the existing Oracle channel. This includes the recruitment and enablement of Oracle partners as well as driving deeper adoption of Oracle's technology and application products within the IT channel. "The main business benefits of ODA for our customers and partners are scalability, flexibility, a great price point for the high performance delivered, and the easily configurable embedded Linux operating system. People welcome a lower point of entry and the ability to grow capacity on demand as their business expands." "Marketing and selling the ODA requires another way of thinking because it is an appliance. We have to transform the ways in which our partners and customers think from buying hardware and software independently to buying complete solutions. Successful early adopters and satisfied customer reactions will certainly help us to sell the ODA. We will have more experience with the product after the first deliveries and installations—end users need to see the power and benefits for themselves." "Our typical ODA customers will be those looking for complete solutions from a single reseller partner who is also able to manage the appliance. They will have enjoyed using Oracle Database but now want a new product that is able to unlock new levels of performance. A higher proportion of potential customers will come from our existing Oracle base, with around 30% from new business, but we intend to evangelise the ODA on the market to see how we can change this balance as all our customers adjust to the concept of 'Hardware and Software, Engineered to Work Together'. -- Back to the welcome page

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  • Why Wifi no longer works 12.04.1

    - by Roger
    starting this morning over wifi (Realtek RTL8188CE) on CLEVO W253HU. May be due to the update before yesterday, more pilot managed, but somehow it worked yesterday. If someone has an idea of the problem. Back command lines: cat /etc/lsb-release DISTRIB_ID=Ubuntu DISTRIB_RELEASE=12.04 DISTRIB_CODENAME=precise DISTRIB_DESCRIPTION="Ubuntu 12.04.1 LTS" lsusb Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub Bus 002 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub Bus 001 Device 002: ID 8087:0024 Intel Corp. Integrated Rate Matching Hub Bus 002 Device 002: ID 8087:0024 Intel Corp. Integrated Rate Matching Hub Bus 002 Device 006: ID 192f:0416 Avago Technologies, Pte. Bus 002 Device 004: ID 5986:0315 Acer, Inc lspci 00:00.0 Host bridge: Intel Corporation 2nd Generation Core Processor Family DRAM Controller (rev 09) 00:02.0 VGA compatible controller: Intel Corporation 2nd Generation Core Processor Family Integrated Graphics Controller (rev 09) 00:16.0 Communication controller: Intel Corporation 6 Series/C200 Series Chipset Family MEI Controller #1 (rev 04) 00:1a.0 USB controller: Intel Corporation 6 Series/C200 Series Chipset Family USB Enhanced Host Controller #2 (rev 05) 00:1b.0 Audio device: Intel Corporation 6 Series/C200 Series Chipset Family High Definition Audio Controller (rev 05) 00:1c.0 PCI bridge: Intel Corporation 6 Series/C200 Series Chipset Family PCI Express Root Port 1 (rev b5) 00:1c.2 PCI bridge: Intel Corporation 6 Series/C200 Series Chipset Family PCI Express Root Port 3 (rev b5) 00:1c.3 PCI bridge: Intel Corporation 6 Series/C200 Series Chipset Family PCI Express Root Port 4 (rev b5) 00:1d.0 USB controller: Intel Corporation 6 Series/C200 Series Chipset Family USB Enhanced Host Controller #1 (rev 05) 00:1f.0 ISA bridge: Intel Corporation HM65 Express Chipset Family LPC Controller (rev 05) 00:1f.2 SATA controller: Intel Corporation 6 Series/C200 Series Chipset Family 6 port SATA AHCI Controller (rev 05) 00:1f.3 SMBus: Intel Corporation 6 Series/C200 Series Chipset Family SMBus Controller (rev 05) 02:00.0 Network controller: Realtek Semiconductor Co., Ltd. RTL8188CE 802.11b/g/n WiFi Adapter (rev 01) 03:00.0 Ethernet controller: JMicron Technology Corp. JMC250 PCI Express Gigabit Ethernet Controller (rev 05) 03:00.1 System peripheral: JMicron Technology Corp. SD/MMC Host Controller (rev 90) 03:00.2 SD Host controller: JMicron Technology Corp. Standard SD Host Controller (rev 90) 03:00.3 System peripheral: JMicron Technology Corp. MS Host Controller (rev 90) lspci -nn | grep -i net 02:00.0 Network controller [0280]: Realtek Semiconductor Co., Ltd. RTL8188CE 802.11b/g/n WiFi Adapter [10ec:8176] (rev 01) 03:00.0 Ethernet controller [0200]: JMicron Technology Corp. JMC250 PCI Express Gigabit Ethernet Controller [197b:0250] (rev 05) lspci -k 00:00.0 Host bridge: Intel Corporation 2nd Generation Core Processor Family DRAM Controller (rev 09) Subsystem: CLEVO/KAPOK Computer Device 4140 Kernel driver in use: agpgart-intel 00:02.0 VGA compatible controller: Intel Corporation 2nd Generation Core Processor Family Integrated Graphics Controller (rev 09) Subsystem: CLEVO/KAPOK Computer Device 4140 Kernel driver in use: i915 Kernel modules: i915 00:16.0 Communication controller: Intel Corporation 6 Series/C200 Series Chipset Family MEI Controller #1 (rev 04) Subsystem: CLEVO/KAPOK Computer Device 4140 Kernel driver in use: mei Kernel modules: mei 00:1a.0 USB controller: Intel Corporation 6 Series/C200 Series Chipset Family USB Enhanced Host Controller #2 (rev 05) Subsystem: CLEVO/KAPOK Computer Device 4140 Kernel driver in use: ehci_hcd 00:1b.0 Audio device: Intel Corporation 6 Series/C200 Series Chipset Family High Definition Audio Controller (rev 05) Subsystem: CLEVO/KAPOK Computer Device 4140 Kernel driver in use: snd_hda_intel Kernel modules: snd-hda-intel 00:1c.0 PCI bridge: Intel Corporation 6 Series/C200 Series Chipset Family PCI Express Root Port 1 (rev b5) Kernel driver in use: pcieport Kernel modules: shpchp 00:1c.2 PCI bridge: Intel Corporation 6 Series/C200 Series Chipset Family PCI Express Root Port 3 (rev b5) Kernel driver in use: pcieport Kernel modules: shpchp 00:1c.3 PCI bridge: Intel Corporation 6 Series/C200 Series Chipset Family PCI Express Root Port 4 (rev b5) Kernel driver in use: pcieport Kernel modules: shpchp 00:1d.0 USB controller: Intel Corporation 6 Series/C200 Series Chipset Family USB Enhanced Host Controller #1 (rev 05) Subsystem: CLEVO/KAPOK Computer Device 4140 Kernel driver in use: ehci_hcd 00:1f.0 ISA bridge: Intel Corporation HM65 Express Chipset Family LPC Controller (rev 05) Subsystem: CLEVO/KAPOK Computer Device 4140 Kernel modules: iTCO_wdt 00:1f.2 SATA controller: Intel Corporation 6 Series/C200 Series Chipset Family 6 port SATA AHCI Controller (rev 05) Subsystem: CLEVO/KAPOK Computer Device 4140 Kernel driver in use: ahci 00:1f.3 SMBus: Intel Corporation 6 Series/C200 Series Chipset Family SMBus Controller (rev 05) Subsystem: CLEVO/KAPOK Computer Device 4140 Kernel modules: i2c-i801 02:00.0 Network controller: Realtek Semiconductor Co., Ltd. RTL8188CE 802.11b/g/n WiFi Adapter (rev 01) Subsystem: Realtek Semiconductor Co., Ltd. Device 9196 Kernel modules: rtl8192ce 03:00.0 Ethernet controller: JMicron Technology Corp. JMC250 PCI Express Gigabit Ethernet Controller (rev 05) Subsystem: CLEVO/KAPOK Computer Device 4140 Kernel driver in use: jme Kernel modules: jme 03:00.1 System peripheral: JMicron Technology Corp. SD/MMC Host Controller (rev 90) Subsystem: CLEVO/KAPOK Computer Device 4140 Kernel driver in use: sdhci-pci Kernel modules: sdhci-pci 03:00.2 SD Host controller: JMicron Technology Corp. Standard SD Host Controller (rev 90) Subsystem: CLEVO/KAPOK Computer Device 4140 Kernel modules: sdhci-pci 03:00.3 System peripheral: JMicron Technology Corp. MS Host Controller (rev 90) Subsystem: CLEVO/KAPOK Computer Device 4140 Kernel driver in use: jmb38x_ms Kernel modules: jmb38x_ms sudo lshw -C network *-network NON-RÉCLAMÉ description: Network controller produit: RTL8188CE 802.11b/g/n WiFi Adapter fabriquant: Realtek Semiconductor Co., Ltd. identifiant matériel: 0 information bus: pci@0000:02:00.0 version: 01 bits: 64 bits horloge: 33MHz fonctionnalités: pm msi pciexpress cap_list configuration: latency=0 ressources: portE/S:e000(taille=256) mémoire:f7d00000-f7d03fff *-network description: Ethernet interface produit: JMC250 PCI Express Gigabit Ethernet Controller fabriquant: JMicron Technology Corp. identifiant matériel: 0 information bus: pci@0000:03:00.0 nom logique: eth0 version: 05 numéro de série: 00:90:f5:c1:c6:45 taille: 100Mbit/s capacité: 1Gbit/s bits: 32 bits horloge: 33MHz fonctionnalités: pm pciexpress msix msi bus_master cap_list rom ethernet physical tp mii 10bt 10bt-fd 100bt 100bt-fd 1000bt 1000bt-fd autonegotiation configuration: autonegotiation=on broadcast=yes driver=jme driverversion=1.0.8 duplex=full ip=192.168.1.54 latency=0 link=yes multicast=yes port=MII speed=100Mbit/s ressources: irq:44 mémoire:f7c20000-f7c23fff portE/S:d100(taille=128) portE/S:d000(taille=256) mémoire:f7c10000-f7c1ffff mémoire:f7c00000-f7c0ffff lsmod Module Size Used by btusb 18288 0 rfcomm 47604 0 bnep 18281 2 bluetooth 180104 11 btusb,rfcomm,bnep parport_pc 32866 0 ppdev 17113 0 binfmt_misc 17540 1 snd_hda_codec_realtek 224173 0 dm_crypt 23125 0 snd_hda_codec_hdmi 32474 0 uvcvideo 72627 0 videodev 98259 1 uvcvideo v4l2_compat_ioctl32 17128 1 videodev snd_hda_intel 33773 2 snd_hda_codec 127706 3 snd_hda_codec_realtek,snd_hda_codec_hdmi,snd_hda_intel snd_hwdep 13668 1 snd_hda_codec snd_pcm 97188 3 snd_hda_codec_hdmi,snd_hda_intel,snd_hda_codec snd_seq_midi 13324 0 snd_rawmidi 30748 1 snd_seq_midi jmb38x_ms 17646 0 psmouse 87692 0 serio_raw 13211 0 memstick 16569 1 jmb38x_ms snd_seq_midi_event 14899 1 snd_seq_midi rtl8192ce 84826 0 rtl8192c_common 75767 1 rtl8192ce rtlwifi 111202 1 rtl8192ce snd_seq 61896 2 snd_seq_midi,snd_seq_midi_event snd_timer 29990 2 snd_pcm,snd_seq snd_seq_device 14540 3 snd_seq_midi,snd_rawmidi,snd_seq mac80211 506816 3 rtl8192ce,rtl8192c_common,rtlwifi mac_hid 13253 0 snd 78855 14 snd_hda_codec_realtek,snd_hda_codec_hdmi,snd_hda_intel,snd_hda_codec,snd_hwdep,snd_pcm,snd_rawmidi,snd_seq,snd_timer,snd_seq_device cfg80211 205544 2 rtlwifi,mac80211 soundcore 15091 1 snd snd_page_alloc 18529 2 snd_hda_intel,snd_pcm mei 41616 0 lp 17799 0 parport 46562 3 parport_pc,ppdev,lp usbhid 47199 0 hid 99559 1 usbhid i915 473035 3 drm_kms_helper 46978 1 i915 drm 242038 4 i915,drm_kms_helper jme 41259 0 i2c_algo_bit 13423 1 i915 sdhci_pci 18826 0 sdhci 33205 1 sdhci_pci wmi 19256 0 video 19596 1 i915 iwconfig lo no wireless extensions. eth0 no wireless extensions. ifconfig eth0 Link encap:Ethernet HWaddr 00:90:f5:c1:c6:45 inet adr:192.168.1.54 Bcast:192.168.1.255 Masque:255.255.255.0 adr inet6: fe80::290:f5ff:fec1:c645/64 Scope:Lien UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 Packets reçus:4513 erreurs:0 :0 overruns:0 frame:0 TX packets:4359 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 lg file transmission:1000 Octets reçus:3471675 (3.4 MB) Octets transmis:712722 (712.7 KB) Interruption:44 lo Link encap:Boucle locale inet adr:127.0.0.1 Masque:255.0.0.0 adr inet6: ::1/128 Scope:Hôte UP LOOPBACK RUNNING MTU:16436 Metric:1 Packets reçus:686 erreurs:0 :0 overruns:0 frame:0 TX packets:686 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 lg file transmission:0 Octets reçus:64556 (64.5 KB) Octets transmis:64556 (64.5 KB) sudo iwlist scan lo Interface doesn't support scanning. eth0 Interface doesn't support scanning. uname -r -m 3.2.0-30-generic x86_64 cat /etc/network/interfaces auto lo iface lo inet loopback nm-tool NetworkManager Tool State: connected (global) - Device: eth0 [Connexion filaire 1] ------------------------------------------ Type: Wired Driver: jme State: connected Default: yes HW Address: 00:90:F5:C1:C6:45 Capabilities: Carrier Detect: yes Speed: 100 Mb/s Wired Properties Carrier: on IPv4 Settings: Address: 192.168.1.54 Prefix: 24 (255.255.255.0) Gateway: 192.168.1.1 DNS: 192.168.1.1 sudo rfkill listrfkill list 1: hci0: Bluetooth Soft blocked: no Hard blocked: no The absence of line "Kernel driver in use:" the return of lspci-k made ??me think that it is not loaded yet but he seems to be. lsmod | grep rtl8192ce rtl8192ce 137478 0 rtlwifi 118749 1 rtl8192ce mac80211 506816 2 rtl8192ce,rtlwifi I found something disturbing in / var / log / syslog Sep 14 11:40:11 pcroger kernel: [ 64.048783] rtl8192ce-0:rtl92c_init_sw_vars():<0-0> Failed to request firmware! Sep 14 11:40:11 pcroger kernel: [ 64.048795] rtlwifi-0:rtl_pci_probe():<0-0> Can't init_sw_vars. Sep 14 11:40:11 pcroger kernel: [ 64.048835] rtl8192ce 0000:02:00.0: PCI INT A disabled Sep 14 11:40:11 pcroger kernel: [ 64.943345] ata1.00: exception Emask 0x0 SAct 0x7fffffff SErr 0x0 action 0x6 frozen Sep 14 11:40:11 pcroger kernel: [ 64.943358] ata1.00: failed command: READ FPDMA QUEUED Sep 14 11:40:11 pcroger kernel: [ 64.943371] ata1.00: cmd 60/00:00:00:68:6a/04:00:0b:00:00/40 tag 0 ncq 524288 in Sep 14 11:40:11 pcroger kernel: [ 64.943374] res 40/00:00:00:00:00/00:00:00:00:00/00 Emask 0x4 (timeout) Sep 14 11:40:11 pcroger kernel: [ 64.943381] ata1.00: status: { DRDY } Ubuntu and takes forever to start (2 min).

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  • Why does an error appear every time I try to open the Ubuntu Software Center? [duplicate]

    - by askubuntu7639
    This question already has an answer here: How do I remove a broken software source? 3 answers There is a glitch on the Ubuntu Software Center and whenever I open it an error appears and it keeps loading and never opens. Why does this happen? I have installed Ubuntu 13.04 on a disk and partitioned it. Please help me and ask for excess information if you need it. If you know of any duplicates please show me them!! This is the output of a question someone asked me. SystemError: E:Type '<!DOCTYPE' is not known on line 1 in source list /etc/apt/sources.list.d/medibuntu.list This next output is the output of cat /etc/apt/sources.list.d/medibuntu.list </div> <div style="float:left;"> <div class="textwidget"><script type="text/javascript"><!-- google_ad_client = "ca-pub-2917661377128354"; /* 160X600 Sidebar UX */ google_ad_slot = "9908287444"; google_ad_width = 160; google_ad_height = 600; //-- Recent Comments <article> <div style="float:left; display:block; margin:0 10px 10px 0; border:1px solid #CCCCCC; padding:3px; width:35px; height:35px;"><img alt='' src='http://0.gravatar.com/avatar/ae5f4503d5f167f1cf62d3e36e8242b6?s=35&amp;d=&amp;r=G' class='avatar avatar-35 photo' height='35' width='35' /></div> <div style="float:left;"> <h4 class="author">Richard Syme</h4> <p class="meta"> <time datetime="2013-09-24" pubdate>September 24, 2013</time> | <a class="permalink" href="http://www.unixmen.com/how-to-customize-you-vlc-hot-keys/#comment-13732">#</a> </p> </div> <div class="content" style="float:left;"><p>I dont have a clear button under the hotkeys. All i want to do is get rid of all hotkeys.</p> </article> <article> <div style="float:left; display:block; margin:0 10px 10px 0; border:1px solid #CCCCCC; padding:3px; width:35px; height:35px;"><img alt='' src='http://1.gravatar.com/avatar/ffabde94437e996a506e31e981bcf8fc?s=35&amp;d=&amp;r=G' class='avatar avatar-35 photo' height='35' width='35' /></div> <div style="float:left;"> <h4 class="author">Abin Thomas Mathew</h4> <p class="meta"> <time datetime="2013-09-24" pubdate>September 24, 2013</time> | <a class="permalink" href="http://www.unixmen.com/install-lamp-server-in-centos-6-4-rhel-6-4/#comment-13727">#</a> </p> </div> <div class="content" style="float:left;"><p>Simple and easy to follow tutorial to install and start of phpMyAdmin. Thank you</p> </article> <article> <div style="float:left; display:block; margin:0 10px 10px 0; border:1px solid #CCCCCC; padding:3px; width:35px; height:35px;"><img alt='' src='http://0.gravatar.com/avatar/499ccc1154e9b8569b87413434220b91?s=35&amp;d=&amp;r=G' class='avatar avatar-35 photo' height='35' width='35' /></div> <div style="float:left;"> <h4 class="author">SK</h4> <p class="meta"> <time datetime="2013-09-24" pubdate>September 24, 2013</time> | <a class="permalink" href="http://www.unixmen.com/munich-giving-ubuntu-linux-cds-citizens/#comment-13725">#</a> </p> </div> <div class="content" style="float:left;"><p>I have Bosslinux and i used it for a while. Now i swiched to Ubuntu 13.04.</p> </article> <article> <div style="float:left; display:block; margin:0 10px 10px 0; border:1px solid #CCCCCC; padding:3px; width:35px; height:35px;"><img alt='' src='http://1.gravatar.com/avatar/3dc2f7140bdd857dcdfe815a6e29aa6b?s=35&amp;d=&amp;r=G' class='avatar avatar-35 photo' height='35' width='35' /></div> <div style="float:left;"> <h4 class="author">Anon</h4> <p class="meta"> <time datetime="2013-09-24" pubdate>September 24, 2013</time> | <a class="permalink" href="http://www.unixmen.com/linus-torvalds-talks-backdoor-linuxcon/#comment-13724">#</a> </p> </div> <div class="content" style="float:left;"><p>Do you know how much extra bloat is in Ubuntu these days? How the hell does anyone really know?</p> </article> <article> <div style="float:left; display:block; margin:0 10px 10px 0; border:1px solid #CCCCCC; padding:3px; width:35px; height:35px;"><img alt='' src='http://1.gravatar.com/avatar/9dd28d1cf5efe754fa58b53c1e6de401?s=35&amp;d=&amp;r=G' class='avatar avatar-35 photo' height='35' width='35' /></div> <div style="float:left;"> <h4 class="author"><a href="http://ambitiousgeeks.blogspot.com/" onclick="javascript:_gaq.push(['_trackEvent','outbound-commentauthor','http://ambitiousgeeks.blogspot.com']);" rel='external nofollow' class='url'>Ambition</a></h4> <p class="meta"> <time datetime="2013-09-24" pubdate>September 24, 2013</time> | <a class="permalink" href="http://www.unixmen.com/linus-torvalds-talks-backdoor-linuxcon/#comment-13723">#</a> </p> </div> <div class="content" style="float:left;"><p>True :)</p> </article> </div> <div style="float:left;"> &nbsp;<script type="text/javascript"> window.___gcfg = {lang: 'en-US'}; (function() {var po = document.createElement("script"); po.type = "text/javascript"; po.async = true;po.src = "https://apis.google.com/js/plusone.js"; var s = document.getElementsByTagName("script")[0]; s.parentNode.insertBefore(po, s); })(); <div class="execphpwidget"></div> </div> <div class="module2"> <div class="recentPost"> <h3 class="module-title2">Favorite Links</h3> <ul class='xoxo blogroll'> http://www.iticy.com']);"Cheap Hosting http://www.tuxmachines.org']);"TuxMachines.org http://www.ubuntugeek.com']);"UbuntuGeek.com http://www.stelinuxhost.com']);"Webdesign & SEO </ul> <img src="http://180016988.r.cdn77.net/wp-content/themes/unimax/images/bigLine.jpg" alt="" /> </div> </div> <div align="center" style="min-height:610px;"> <div class="execphpwidget"></div> <div class="textwidget"><a rel="license" href="http://creativecommons.org/licenses/by-nc-nd/3.0/deed.en_US" onclick="javascript:_gaq.push(['_trackEvent','outbound-widget','http://creativecommons.org']);"><img alt="Creative Commons License" style="border-width:0" src="http://i.creativecommons.org/l/by-nc-nd/3.0/88x31.png" /></a><br />This work by <a xmlns:cc="http://creativecommons.org/ns#" href="unixmen.com" property="cc:attributionName" rel="cc:attributionURL">unixmen.com</a> is licensed under a <a rel="license" href="http://creativecommons.org/licenses/by-nc-nd/3.0/deed.en_US" >Creative Commons Attribution-NonCommercial-NoDerivs 3.0 Unported License</a>.</div> </div> </div> <!-- #primary .widget-area --> </div> Unixmen Archive Select Month September 2013 August 2013 July 2013 June 2013 May 2013 April 2013 March 2013 February 2013 January 2013 December 2012 November 2012 October 2012 September 2012 August 2012 July 2012 June 2012 May 2012 April 2012 March 2012 February 2012 January 2012 December 2011 November 2011 October 2011 September 2011 August 2011 July 2011 June 2011 May 2011 April 2011 March 2011 February 2011 January 2011 December 2010 November 2010 October 2010 September 2010 August 2010 July 2010 June 2010 May 2010 April 2010 March 2010 February 2010 January 2010 December 2009 November 2009 October 2009 September 2009 August 2009 July 2009 June 2009 May 2009 April 2009 March 2009 February 2009 January 2009 December 2008 Tags Cloudandroid apache browser Centos chrome command line Debian eyecandy Fedora firefox games gaming gnome google karmic koala kde libreoffice Linux linux distribution LinuxMint lucid lynx maverick meerkat mysql news oneiric ocelot openoffice opensource opensuse oracle ppa Precise Pangolin release RHEL security server software themes tools ubuntu unix upgrade virtualbox vlc windows wine Unixmen Twitts Firefox 16, a treat for developers http://t.co/cnd27CzT Ubuntu 12.10 ‘Quantal Quetzal’: Beta 2 Sneak Peek http://t.co/hd4LwDOy Top 5 security Myths about Linux; and their realities http://t.co/zO1LgHST About Us Advertising Sitemap Privacy Contact Us Hire Us Copyright © 2008-2013 Unixmen.com . Maintained by Unixmen . /* */ jQuery(document).on('ready post-load', easy_fancybox_handler ); http://www.w3-edge.com/wordpress-plugins/ Page Caching using apc Database Caching 3/186 queries in 0.035 seconds using apc Content Delivery Network via 180016988.r.cdn77.net Served from: www.unixmen.com @ 2013-09-25 01:38:14 by W3 Total Cache

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  • SQL SERVER – Weekly Series – Memory Lane – #007

    - by pinaldave
    Here is the list of selected articles of SQLAuthority.com across all these years. Instead of just listing all the articles I have selected a few of my most favorite articles and have listed them here with additional notes below it. Let me know which one of the following is your favorite article from memory lane. 2006 Find Stored Procedure Related to Table in Database – Search in All Stored Procedure In 2006 I wrote a small script which will help user  find all the Stored Procedures (SP) which are related to one or more specific tables. This was quite a popular script however, in SQL Server 2012 the same can be achieved using new DMV sys.sql-expression_dependencies. I recently blogged about it over Find Referenced or Referencing Object in SQL Server using sys.sql_expression_dependencies. 2007 SQL SERVER – Versions, CodeNames, Year of Release 1993 – SQL Server 4.21 for Windows NT 1995 – SQL Server 6.0, codenamed SQL95 1996 – SQL Server 6.5, codenamed Hydra 1999 – SQL Server 7.0, codenamed Sphinx 1999 – SQL Server 7.0 OLAP, codenamed Plato 2000 – SQL Server 2000 32-bit, codenamed Shiloh (version 8.0) 2003 – SQL Server 2000 64-bit, codenamed Liberty 2005 – SQL Server 2005, codenamed Yukon (version 9.0) 2008 – SQL Server 2008, codenamed Katmai (version 10.0) 2011 – SQL Server 2008, codenamed Denali (version 11.0) Search String in Stored Procedure Searching sting in the stored procedure is one of the most frequent task developer do. They might be searching for a table, view or any other details. I have written a script to do the same in SQL Server 2000 and SQL Server 2005. This is worth bookmarking blog post. There is an alternative way to do the same as well here is the example. 2008 SQL SERVER – Refresh Database Using T-SQL NO! Some of the questions have a single answer NO! You may want to read the question in the original blog post. I had a great time saying No! SQL SERVER – Delete Backup History – Cleanup Backup History SQL Server stores history of all the taken backup forever. History of all the backup is stored in the msdb database. Many times older history is no more required. Following Stored Procedure can be executed with a parameter which takes days of history to keep. In the following example 30 is passed to keep a history of month. 2009 Stored Procedure are Compiled on First Run – SP taking Longer to Run First Time Is stored procedure pre-compiled? Why the Stored Procedure takes a long time to run for the first time?  This is a very common questions often discussed by developers and DBAs. There is an absolutely definite answer but the question has been discussed forever. There is a misconception that stored procedures are pre-compiled. They are not pre-compiled, but compiled only during the first run. For every subsequent runs, it is for sure pre-compiled. Read the entire article for example and demonstration. Removing Key Lookup – Seek Predicate – Predicate – An Interesting Observation Related to Datatypes This is one of the most important performance tuning lesson on my blog. I suggest this weekend you spend time reading them and let me know what you think about the concepts which I have demonstrated in the four part series. Part 1 | Part 2 | Part 3 | Part 4 Seek Predicate is the operation that describes the b-tree portion of the Seek. Predicate is the operation that describes the additional filter using non-key columns. Based on the description, it is very clear that Seek Predicate is better than Predicate as it searches indexes whereas in Predicate, the search is on non-key columns – which implies that the search is on the data in page files itself. Policy Based Management – Create, Evaluate and Fix Policies This article will cover the most spectacular feature of SQL Server – Policy-based management and how the configuration of SQL Server with policy-based management architecture can make a powerful difference. Policy based management is loaded with several advantages. It can help you implement various policies for reliable configuration of the system. It also provides additional administration assistance to DBAs and helps them effortlessly manage various tasks of SQL Server across the enterprise. 2010 Recycle Error Log – Create New Log file without Server Restart Once I observed a DBA to restaring the SQL Server when he needed new error log file. This was funny and sad both at the same time. There is no need to restart the server to create a new log file or recycle the log file. You can run sp_cycle_errorlog and achieve the same result. Get Database Backup History for a Single Database Simple but effective script! Reducing CXPACKET Wait Stats for High Transactional Database The subject is very complex and I have done my best to simplify the concept. In simpler words, when a parallel operation is created for SQL Query, there are multiple threads for a single query. Each query deals with a different set of the data (or rows). Due to some reasons, one or more of the threads lag behind, creating the CXPACKET Wait Stat. Threads which came first have to wait for the slower thread to finish. The Wait by a specific completed thread is called CXPACKET Wait Stat. Information Related to DATETIME and DATETIME2 There are quite a lot of confusion with DATETIME and DATETIME2. DATETIME2 is also one of the underutilized datatype of SQL Server.  In this blog post I have written a follow up of the my earlier datetime series where I clarify a few of the concepts related to datetime. Difference Between GETDATE and SYSDATETIME Difference Between DATETIME and DATETIME2 – WITH GETDATE Difference Between DATETIME and DATETIME2 2011 Introduction to CUME_DIST – Analytic Functions Introduced in SQL Server 2012 SQL Server 2012 introduces new analytical function CUME_DIST(). This function provides cumulative distribution value. It will be very difficult to explain this in words so I will attempt small example to explain you this function. Instead of creating new table, I will be using AdventureWorks sample database as most of the developer uses that for experiment. Introduction to FIRST _VALUE and LAST_VALUE – Analytic Functions Introduced in SQL Server 2012 SQL Server 2012 introduces new analytical functions FIRST_VALUE() and LAST_VALUE(). This function returns first and last value from the list. It will be very difficult to explain this in words so I’d like to attempt to explain its function through a brief example. Instead of creating a new table, I will be using the AdventureWorks sample database as most developers use that for experiment purposes. OVER clause with FIRST _VALUE and LAST_VALUE – Analytic Functions Introduced in SQL Server 2012 – ROWS BETWEEN UNBOUNDED PRECEDING AND UNBOUNDED FOLLOWING “Don’t you think there is bug in your first example where FIRST_VALUE is remain same but the LAST_VALUE is changing every line. I think the LAST_VALUE should be the highest value in the windows or set of result.” Puzzle – Functions FIRST_VALUE and LAST_VALUE with OVER clause and ORDER BY You can see that row number 2, 3, 4, and 5 has same SalesOrderID = 43667. The FIRST_VALUE is 78 and LAST_VALUE is 77. Now if these function was working on maximum and minimum value they should have given answer as 77 and 80 respectively instead of 78 and 77. Also the value of FIRST_VALUE is greater than LAST_VALUE 77. Why? Explain in detail. Introduction to LEAD and LAG – Analytic Functions Introduced in SQL Server 2012 SQL Server 2012 introduces new analytical function LEAD() and LAG(). This functions accesses data from a subsequent row (for lead) and previous row (for lag) in the same result set without the use of a self-join . It will be very difficult to explain this in words so I will attempt small example to explain you this function. Instead of creating new table, I will be using AdventureWorks sample database as most of the developer uses that for experiment. A Real Story of Book Getting ‘Out of Stock’ to A 25% Discount Story Available Our book was out of stock in 48 hours of it was arrived in stock! We got call from the online store with a request for more copies within 12 hours. But we had printed only as many as we had sent them. There were no extra copies. We finally talked to the printer to get more copies. However, due to festivals and holidays the copies could not be shipped to the online retailer for two days. We knew for sure that they were going to be out of the book for 48 hours. This is the story of how we overcame that situation! Reference: Pinal Dave (http://blog.sqlauthority.com) Filed under: Memory Lane, PostADay, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, T SQL, Technology

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  • Summary of the Solaris 11 webcast's livechat QnA session

    - by Karoly Vegh
    This is a followup post to the previous summary on the "What's new with Solaris 11 since the launch" webcast. That webcast has had a chatroom for a live Questions and Answers session running. I went through the archive of those and compiled a list of some of the (IMHO) most relevant and most frequently asked questions, I'd like to share. This is the first part, covering the QnA of Session I and II of the webcast, in a followup post we can have a look of the rest of the sessions if required - let me know in the comments. Also, should you have questions, as usual, feel free to ask those there, too.  ...and here come the answered questions:  When will Exadata be based on Solaris in place of Oracle Enterprise Linux?Exadata offers both Solaris 11 or Oracle Enterprise Linux.  The choice can be made at deployment time based on your OS needs.What are all other benefits and futures avilable in solaris 11 (cloud O.S.) compared to cloud based Red Hat Linux and Windows?suggest you check out our cloud white paper for a view of this. Also the OTN Solaris 11 page has some good articles. Here are the links:  http://www.oracle.com/technetwork/server-storage/solaris11/documentation/o11-106-sol11-cloud-501066.pdf http://www.oracle.com/technetwork/server-storage/solaris11/overview/index.htmlWill 11.1 have a more complete IPS respository for Oracle and FOSS software?Yes, we are adding additional packages to the various package repositories. Since Solaris 11 was launched, both the Oracle Solaris Studio tools as well as Oracle Solaris Cluster have been made available along with numerous new FOSS packages. We will continue to be adding additional Oracle products and open source packages in the future. Will Exadata be based on Sparc in place of intel-amd x86 in next future ?We can't publically discuss futures, but we actually have a SPARC version of Exadata today, it's called SuperCluster, this is such a powerfull multipurpose system that it actually have multiple personalities built into one system: Exadata, Exalogic, and it can be a general purpose platform if you want. Have I understood this right? Livepatching KSplice-style is coming to Solaris 11 too?We're looking at that for certain types of Solaris patches in the future.Will there be a security framework like SST/JASS for Solaris 11?We can't talk about the future projects on a public forum, but we recognize the need for SST/JASS and want to address this as soon as possible. On the other side there are a whole bunch of "best practices" that are now embedded into Solaris 11 by default, so out of the box Solaris 11 should already address part of what SST/JASS gave you. (For example we did a lot of work on improving the auditing performance so that we can now have it turned on by default). On x86 can install VirtualBox in a Zone and use that to host other OSes.Yes, this was one of the first things we made sure would work when we acquired VirtualBox when we were still Sun Microsystems. If I have a Solaris 11 Control Domain on a T-series, can I run a Solaris 10 Ldom with Solaris 8 branded containers?Yes, you can.Is Oracle Solaris free or do we need to purchase?Solaris is free, the entitlement to run it comes either with a Sun system (new or historical) or for 3rd party systems the entitlement comes with a support contract. Note that for production use you will be expected to get a support contract. If you don't want to use the Solaris system (Sun or 3rd party) for production use (i.e. development) you can get an OTN license on the Oracle Technical Network website. Will encryption and deduplication both work on a share?This should work at the same time. What approaches does Solaris use to monitor usage?There are many different tools in Solaris to monitor usage. The main ones are the "stats" (vmstat, mpstat, prstat, ...), the kstat interface, and DTrace (to get details you couldn't see before). And then there are layered tools that can interface with these tools (Ops Center, BMC, CA, Tivoli, ...) Apart little-endian, big-endian how is it easy to port Solaris applications on Sparc to x86 and vice-versa ?Very easy. Except for certain hardware specific applications (those that utilize hardware specific drivers), all of the same Oracle Solaris APIs exist for all architectures. Is IPS based patching aware of the fact that zones can reside on ZFS and move from one physical server to another ?IPS is definitely aware of zones and uses ZFS to support boot environments for non-global zones in the same way that's used for the global zone. With respect to moving a zone from one physical server to another, Solaris 11 supports to the same zone attach/deattach method that was introduced in Solaris 10. Is vnic support in Ldoms planned?This is currently being investigated for a future LDOM release. Is it possible with the new patching system to build a system later with the same patch level as a system built a few months earlier?Yes, you can choose/define exactly which version should go to the system and it will always put the same bits in place. The technical answer is that you choose the version of the "entire" package you want on the system and the rest flows from there. Is it in the plans to allow zones to add/remove zpools to running zones dynamically in future updates?Work in this area is currently under investigation. Any plans to realese Solaris 11 source code? i.e. opensolaris?We currently can't comment on publicly releasing the source code. If you need/want this access please let your Oracle account team know. What about VirtualBox and Solaris11 for virtualization?Solaris 11 works great with VirtualBox, as both a client and a host system. Will Oracle DB software eventually be supplied as IPS packages? When?We don't have a date yet but this is actively being worked on. What are the new artifacts in Oracle Solaris 11 than the previous versions?There are quite a few actually. The best start is to look at our "Evaluate Solaris 11" page, and there you also can find a Transition Guide. http://www.oracle.com/technetwork/server-storage/solaris11/overview/evaluate-1530234.html So, this seems just like RedHat's YUM environment?IPS offers certain features beyond those in YUM or other packaging systems. For example, IPS works with ZFS and Solaris Boot Environments to provide a safe environment for software lifecycle management so that changes can be reverted by switching to an older boot environment. With Zones on solaris 11, can I do paravirtualitation?The great thing about zones is you don't *need* paravirtualization. You're making the same direct kernel calls that you would outside of a zone.  It's an incredibly significant performance win over hypervisor-based virtualization. Are zones/containers officially supported to run Oracle Databases?  EBIZ?Hi Calvin, the answer is yes, here is the support matrix for DB:  http://www.oracle.com/technetwork/database/virtualizationmatrix-172995.html I've found some nasty bugs in Solaris 11 (one of which today) that have been fixed in community forks (i.e., Illumos). Will Oracle ever restart collaboration with the community?We continue to work with the community, just not as open on all projects as we did before (For example IPS is an open project) and the source of more than half of the Solaris packages is posted on our opensource websites. I can't comment on what we will do in the future. And with regards to bugs please file them through the support organization and we will get them resolved. Is zpool vdev removal on-the fly now possible ?This issue is actively being investigated although we don't have a date for when this feature will be available. Is pgstat now the official replacement for corestat ?It's intended to provide similar functionality Where are the opensource website?For Oracle Solaris, visit http://www.oracle.com/technetwork/opensource/systems-solaris-1562786.html As a cloud-scale virtualization, is it going to be easier to move zones between machines? maybe even automatic in case of a hardware failure?Hi Gashaw, we already have customers that have implemented what they refer to as "flying zones" that they can move around very easily. They use Solaris Cluster to do this. What about VMware vMotion like feature?We have secure live migration with both Logical Domains on SPARC T series systems, and with Oracle VM on x86 systems. When running Solaris 10/11 on an enterprise server with a lot of zones, what are best practises commands to show the system is running fine? (has enough hardware resources). For example CPU / Memory / I/O / system load. What are the recommended values?For Solaris 11, look into the new zonestat(1M) command that provides a great deal of information about zone utilization. In addition, there is new work underway in providing additional observability in areas such as per-zone file system I/O. Java optimizations done with Solaris 11? For X86 platforms too? Where can I find more detail about this?There is lots of work that go into optimizing Java for Oracle Solaris 10 & 11 on both SPARC and x86. See http://www.oracle.com/technetwork/articles/servers-storage-dev/solarisforjavadevelop-168642.pdf What is meant by "ZFS Shadow Migration"?It's a way to migrate data from another file system to ZFS: http://docs.oracle.com/cd/E23824_01/html/E24456/filesystem-3.html Is flash archive available with S11?Flash archive is not.  There is a procedure for disaster recovery, and we're working on a modern archive-based deployment tool for a future update.  The disaster recovery tool is here: http://www.oracle.com/technetwork/articles/servers-storage-admin/o11-091-sol-dis-recovery-489183.html  You can also use Distribution Constructor to build common golden images. Will solaris 11 be available on the ODA soon?The idea's under evaluation -- we'll share your interest with the team. What steps can be taken to ensure that breaches of security are identified quickly?There are a number of tools, including the "bart" tool and "pkg verify" to ensure that software has not been compromised.  Solaris Audit can also be used to detect unauthorized access.  You can also use Immutable Zones to protect against compromise.  There are a wide variety of security tools, and I've covered only a few. What is the relation from solaris to java 7 speed optimization?There is constant work done between the Oracle Solaris and Java teams on performance optimizations. See http://docs.oracle.com/javase/7/docs/technotes/guides/vm/performance-enhancements-7.html for examples. What is the difference in the Solaris 11 installation compared to solaris 10 ? where i can find the document describing basic repository concepts ?The best place to start is: http://www.oracle.com/technetwork/server-storage/solaris11/index.html Hope you found the post useful. For questions, input, requests for the second half of the QnA, please find the comment section below.  -- charlie  

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  • Why unhandled exceptions are useful

    - by Simon Cooper
    It’s the bane of most programmers’ lives – an unhandled exception causes your application or webapp to crash, an ugly dialog gets displayed to the user, and they come complaining to you. Then, somehow, you need to figure out what went wrong. Hopefully, you’ve got a log file, or some other way of reporting unhandled exceptions (obligatory employer plug: SmartAssembly reports an application’s unhandled exceptions straight to you, along with the entire state of the stack and variables at that point). If not, you have to try and replicate it yourself, or do some psychic debugging to try and figure out what’s wrong. However, it’s good that the program crashed. Or, more precisely, it is correct behaviour. An unhandled exception in your application means that, somewhere in your code, there is an assumption that you made that is actually invalid. Coding assumptions Let me explain a bit more. Every method, every line of code you write, depends on implicit assumptions that you have made. Take this following simple method, that copies a collection to an array and includes an item if it isn’t in the collection already, using a supplied IEqualityComparer: public static T[] ToArrayWithItem( ICollection<T> coll, T obj, IEqualityComparer<T> comparer) { // check if the object is in collection already // using the supplied comparer foreach (var item in coll) { if (comparer.Equals(item, obj)) { // it's in the collection already // simply copy the collection to an array // and return it T[] array = new T[coll.Count]; coll.CopyTo(array, 0); return array; } } // not in the collection // copy coll to an array, and add obj to it // then return it T[] array = new T[coll.Count+1]; coll.CopyTo(array, 0); array[array.Length-1] = obj; return array; } What’s all the assumptions made by this fairly simple bit of code? coll is never null comparer is never null coll.CopyTo(array, 0) will copy all the items in the collection into the array, in the order defined for the collection, starting at the first item in the array. The enumerator for coll returns all the items in the collection, in the order defined for the collection comparer.Equals returns true if the items are equal (for whatever definition of ‘equal’ the comparer uses), false otherwise comparer.Equals, coll.CopyTo, and the coll enumerator will never throw an exception or hang for any possible input and any possible values of T coll will have less than 4 billion items in it (this is a built-in limit of the CLR) array won’t be more than 2GB, both on 32 and 64-bit systems, for any possible values of T (again, a limit of the CLR) There are no threads that will modify coll while this method is running and, more esoterically: The C# compiler will compile this code to IL according to the C# specification The CLR and JIT compiler will produce machine code to execute the IL on the user’s computer The computer will execute the machine code correctly That’s a lot of assumptions. Now, it could be that all these assumptions are valid for the situations this method is called. But if this does crash out with an exception, or crash later on, then that shows one of the assumptions has been invalidated somehow. An unhandled exception shows that your code is running in a situation which you did not anticipate, and there is something about how your code runs that you do not understand. Debugging the problem is the process of learning more about the new situation and how your code interacts with it. When you understand the problem, the solution is (usually) obvious. The solution may be a one-line fix, the rewrite of a method or class, or a large-scale refactoring of the codebase, but whatever it is, the fix for the crash will incorporate the new information you’ve gained about your own code, along with the modified assumptions. When code is running with an assumption or invariant it depended on broken, then the result is ‘undefined behaviour’. Anything can happen, up to and including formatting the entire disk or making the user’s computer sentient and start doing a good impression of Skynet. You might think that those can’t happen, but at Halting problem levels of generality, as soon as an assumption the code depended on is broken, the program can do anything. That is why it’s important to fail-fast and stop the program as soon as an invariant is broken, to minimise the damage that is done. What does this mean in practice? To start with, document and check your assumptions. As with most things, there is a level of judgement required. How you check and document your assumptions depends on how the code is used (that’s some more assumptions you’ve made), how likely it is a method will be passed invalid arguments or called in an invalid state, how likely it is the assumptions will be broken, how expensive it is to check the assumptions, and how bad things are likely to get if the assumptions are broken. Now, some assumptions you can assume unless proven otherwise. You can safely assume the C# compiler, CLR, and computer all run the method correctly, unless you have evidence of a compiler, CLR or processor bug. You can also assume that interface implementations work the way you expect them to; implementing an interface is more than simply declaring methods with certain signatures in your type. The behaviour of those methods, and how they work, is part of the interface contract as well. For example, for members of a public API, it is very important to document your assumptions and check your state before running the bulk of the method, throwing ArgumentException, ArgumentNullException, InvalidOperationException, or another exception type as appropriate if the input or state is wrong. For internal and private methods, it is less important. If a private method expects collection items in a certain order, then you don’t necessarily need to explicitly check it in code, but you can add comments or documentation specifying what state you expect the collection to be in at a certain point. That way, anyone debugging your code can immediately see what’s wrong if this does ever become an issue. You can also use DEBUG preprocessor blocks and Debug.Assert to document and check your assumptions without incurring a performance hit in release builds. On my coding soapbox… A few pet peeves of mine around assumptions. Firstly, catch-all try blocks: try { ... } catch { } A catch-all hides exceptions generated by broken assumptions, and lets the program carry on in an unknown state. Later, an exception is likely to be generated due to further broken assumptions due to the unknown state, causing difficulties when debugging as the catch-all has hidden the original problem. It’s much better to let the program crash straight away, so you know where the problem is. You should only use a catch-all if you are sure that any exception generated in the try block is safe to ignore. That’s a pretty big ask! Secondly, using as when you should be casting. Doing this: (obj as IFoo).Method(); or this: IFoo foo = obj as IFoo; ... foo.Method(); when you should be doing this: ((IFoo)obj).Method(); or this: IFoo foo = (IFoo)obj; ... foo.Method(); There’s an assumption here that obj will always implement IFoo. If it doesn’t, then by using as instead of a cast you’ve turned an obvious InvalidCastException at the point of the cast that will probably tell you what type obj actually is, into a non-obvious NullReferenceException at some later point that gives you no information at all. If you believe obj is always an IFoo, then say so in code! Let it fail-fast if not, then it’s far easier to figure out what’s wrong. Thirdly, document your assumptions. If an algorithm depends on a non-trivial relationship between several objects or variables, then say so. A single-line comment will do. Don’t leave it up to whoever’s debugging your code after you to figure it out. Conclusion It’s better to crash out and fail-fast when an assumption is broken. If it doesn’t, then there’s likely to be further crashes along the way that hide the original problem. Or, even worse, your program will be running in an undefined state, where anything can happen. Unhandled exceptions aren’t good per-se, but they give you some very useful information about your code that you didn’t know before. And that can only be a good thing.

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  • Blank Screen at boot Ubuntu 12.04 - nvidia-current - Macbook Air 3,2

    - by soulnafein
    I've installed nvidia-current using the Additional Drivers application in Ubuntu 12.04. I need those drivers so I can use accelerated WebGL. After installing the drivers, and rebooting X fails to start and I have a frozen system/dark screen. Below is the content of Xorg.0.log How can I fix this problem? [ 4.666] X.Org X Server 1.11.3 Release Date: 2011-12-16 [ 4.666] X Protocol Version 11, Revision 0 [ 4.666] Build Operating System: Linux 2.6.42-23-generic x86_64 Ubuntu [ 4.666] Current Operating System: Linux david-macbook-air 3.2.0-34-generic #53-Ubuntu SMP Thu Nov 15 10:48:16 UTC 2012 x86_64 [ 4.666] Kernel command line: BOOT_IMAGE=/boot/vmlinuz-3.2.0-34-generic root=UUID=b3d5ae2a-72af-4ef9-b775-0d40b5f80f9b ro quiet splash vt.handoff=7 [ 4.666] Build Date: 29 August 2012 12:12:33AM [ 4.666] xorg-server 2:1.11.4-0ubuntu10.8 (For technical support please see http://www.ubuntu.com/support) [ 4.666] Current version of pixman: 0.24.4 [ 4.666] Before reporting problems, check http://wiki.x.org to make sure that you have the latest version. [ 4.666] Markers: (--) probed, (**) from config file, (==) default setting, (++) from command line, (!!) notice, (II) informational, (WW) warning, (EE) error, (NI) not implemented, (??) unknown. [ 4.666] (==) Log file: "/var/log/Xorg.0.log", Time: Thu Dec 13 10:18:02 2012 [ 4.668] (==) Using system config directory "/usr/share/X11/xorg.conf.d" [ 4.668] (==) No Layout section. Using the first Screen section. [ 4.668] (==) No screen section available. Using defaults. [ 4.668] (**) |-->Screen "Default Screen Section" (0) [ 4.668] (**) | |-->Monitor "<default monitor>" [ 4.668] (==) No monitor specified for screen "Default Screen Section". Using a default monitor configuration. [ 4.668] (==) Automatically adding devices [ 4.668] (==) Automatically enabling devices [ 4.668] (WW) The directory "/usr/share/fonts/X11/cyrillic" does not exist. [ 4.668] Entry deleted from font path. [ 4.668] (WW) The directory "/usr/share/fonts/X11/100dpi/" does not exist. [ 4.668] Entry deleted from font path. [ 4.669] (WW) The directory "/usr/share/fonts/X11/75dpi/" does not exist. [ 4.669] Entry deleted from font path. [ 4.669] (WW) The directory "/usr/share/fonts/X11/100dpi" does not exist. [ 4.669] Entry deleted from font path. [ 4.669] (WW) The directory "/usr/share/fonts/X11/75dpi" does not exist. [ 4.669] Entry deleted from font path. [ 4.669] (WW) The directory "/var/lib/defoma/x-ttcidfont-conf.d/dirs/TrueType" does not exist. [ 4.669] Entry deleted from font path. [ 4.669] (==) FontPath set to: /usr/share/fonts/X11/misc, /usr/share/fonts/X11/Type1, built-ins [ 4.669] (==) ModulePath set to "/usr/lib/x86_64-linux-gnu/xorg/extra-modules,/usr/lib/xorg/extra-modules,/usr/lib/xorg/modules" [ 4.669] (II) The server relies on udev to provide the list of input devices. If no devices become available, reconfigure udev or disable AutoAddDevices. [ 4.669] (II) Loader magic: 0x7f6222467b00 [ 4.669] (II) Module ABI versions: [ 4.669] X.Org ANSI C Emulation: 0.4 [ 4.669] X.Org Video Driver: 11.0 [ 4.669] X.Org XInput driver : 16.0 [ 4.669] X.Org Server Extension : 6.0 [ 4.670] (--) PCI:*(0:2:0:0) 10de:08a3:106b:00d3 rev 162, Mem @ 0x92000000/16777216, 0x80000000/268435456, 0x90000000/33554432, I/O @ 0x00001000/128, BIOS @ 0x????????/131072 [ 4.670] (II) Open ACPI successful (/var/run/acpid.socket) [ 4.670] (II) LoadModule: "extmod" [ 4.671] (II) Loading /usr/lib/xorg/modules/extensions/libextmod.so [ 4.671] (II) Module extmod: vendor="X.Org Foundation" [ 4.671] compiled for 1.11.3, module version = 1.0.0 [ 4.671] Module class: X.Org Server Extension [ 4.671] ABI class: X.Org Server Extension, version 6.0 [ 4.671] (II) Loading extension MIT-SCREEN-SAVER [ 4.671] (II) Loading extension XFree86-VidModeExtension [ 4.671] (II) Loading extension XFree86-DGA [ 4.671] (II) Loading extension DPMS [ 4.671] (II) Loading extension XVideo [ 4.671] (II) Loading extension XVideo-MotionCompensation [ 4.671] (II) Loading extension X-Resource [ 4.671] (II) LoadModule: "dbe" [ 4.671] (II) Loading /usr/lib/xorg/modules/extensions/libdbe.so [ 4.671] (II) Module dbe: vendor="X.Org Foundation" [ 4.671] compiled for 1.11.3, module version = 1.0.0 [ 4.671] Module class: X.Org Server Extension [ 4.671] ABI class: X.Org Server Extension, version 6.0 [ 4.671] (II) Loading extension DOUBLE-BUFFER [ 4.671] (II) LoadModule: "glx" [ 4.671] (II) Loading /usr/lib/x86_64-linux-gnu/xorg/extra-modules/libglx.so [ 4.869] (II) Module glx: vendor="NVIDIA Corporation" [ 4.869] compiled for 4.0.2, module version = 1.0.0 [ 4.869] Module class: X.Org Server Extension [ 4.869] (II) NVIDIA GLX Module 295.40 Thu Apr 5 21:57:38 PDT 2012 [ 4.869] (II) Loading extension GLX [ 4.869] (II) LoadModule: "record" [ 4.870] (II) Loading /usr/lib/xorg/modules/extensions/librecord.so [ 4.870] (II) Module record: vendor="X.Org Foundation" [ 4.870] compiled for 1.11.3, module version = 1.13.0 [ 4.870] Module class: X.Org Server Extension [ 4.870] ABI class: X.Org Server Extension, version 6.0 [ 4.870] (II) Loading extension RECORD [ 4.870] (II) LoadModule: "dri" [ 4.870] (II) Loading /usr/lib/xorg/modules/extensions/libdri.so [ 4.870] (II) Module dri: vendor="X.Org Foundation" [ 4.870] compiled for 1.11.3, module version = 1.0.0 [ 4.870] ABI class: X.Org Server Extension, version 6.0 [ 4.870] (II) Loading extension XFree86-DRI [ 4.870] (II) LoadModule: "dri2" [ 4.871] (II) Loading /usr/lib/xorg/modules/extensions/libdri2.so [ 4.871] (II) Module dri2: vendor="X.Org Foundation" [ 4.871] compiled for 1.11.3, module version = 1.2.0 [ 4.871] ABI class: X.Org Server Extension, version 6.0 [ 4.871] (II) Loading extension DRI2 [ 4.871] (==) Matched nvidia as autoconfigured driver 0 [ 4.871] (==) Matched nouveau as autoconfigured driver 1 [ 4.871] (==) Matched nv as autoconfigured driver 2 [ 4.871] (==) Matched vesa as autoconfigured driver 3 [ 4.871] (==) Matched fbdev as autoconfigured driver 4 [ 4.871] (==) Assigned the driver to the xf86ConfigLayout [ 4.871] (II) LoadModule: "nvidia" [ 4.871] (II) Loading /usr/lib/x86_64-linux-gnu/xorg/extra-modules/nvidia_drv.so [ 4.887] (II) Module nvidia: vendor="NVIDIA Corporation" [ 4.887] compiled for 4.0.2, module version = 1.0.0 [ 4.887] Module class: X.Org Video Driver [ 4.892] (II) LoadModule: "nouveau" [ 4.894] (II) Loading /usr/lib/xorg/modules/drivers/nouveau_drv.so [ 4.894] (II) Module nouveau: vendor="X.Org Foundation" [ 4.894] compiled for 1.11.3, module version = 1.0.2 [ 4.894] Module class: X.Org Video Driver [ 4.894] ABI class: X.Org Video Driver, version 11.0 [ 4.894] (II) LoadModule: "nv" [ 4.895] (WW) Warning, couldn't open module nv [ 4.895] (II) UnloadModule: "nv" [ 4.895] (II) Unloading nv [ 4.895] (EE) Failed to load module "nv" (module does not exist, 0) [ 4.895] (II) LoadModule: "vesa" [ 4.895] (II) Loading /usr/lib/xorg/modules/drivers/vesa_drv.so [ 4.896] (II) Module vesa: vendor="X.Org Foundation" [ 4.896] compiled for 1.11.3, module version = 2.3.0 [ 4.896] Module class: X.Org Video Driver [ 4.896] ABI class: X.Org Video Driver, version 11.0 [ 4.896] (II) LoadModule: "fbdev" [ 4.896] (II) Loading /usr/lib/xorg/modules/drivers/fbdev_drv.so [ 4.896] (II) Module fbdev: vendor="X.Org Foundation" [ 4.896] compiled for 1.11.3, module version = 0.4.2 [ 4.896] ABI class: X.Org Video Driver, version 11.0 [ 4.896] (==) Matched nvidia as autoconfigured driver 0 [ 4.896] (==) Matched nouveau as autoconfigured driver 1 [ 4.896] (==) Matched nv as autoconfigured driver 2 [ 4.896] (==) Matched vesa as autoconfigured driver 3 [ 4.896] (==) Matched fbdev as autoconfigured driver 4 [ 4.896] (==) Assigned the driver to the xf86ConfigLayout [ 4.896] (II) LoadModule: "nvidia" [ 4.896] (II) Loading /usr/lib/x86_64-linux-gnu/xorg/extra-modules/nvidia_drv.so [ 4.896] (II) Module nvidia: vendor="NVIDIA Corporation" [ 4.896] compiled for 4.0.2, module version = 1.0.0 [ 4.896] Module class: X.Org Video Driver [ 4.896] (II) UnloadModule: "nvidia" [ 4.896] (II) Unloading nvidia [ 4.896] (II) Failed to load module "nvidia" (already loaded, 32610) [ 4.896] (II) LoadModule: "nouveau" [ 4.897] (II) Loading /usr/lib/xorg/modules/drivers/nouveau_drv.so [ 4.897] (II) Module nouveau: vendor="X.Org Foundation" [ 4.897] compiled for 1.11.3, module version = 1.0.2 [ 4.897] Module class: X.Org Video Driver [ 4.897] ABI class: X.Org Video Driver, version 11.0 [ 4.897] (II) UnloadModule: "nouveau" [ 4.897] (II) Unloading nouveau [ 4.897] (II) Failed to load module "nouveau" (already loaded, 32610) [ 4.897] (II) LoadModule: "nv" [ 4.897] (WW) Warning, couldn't open module nv [ 4.897] (II) UnloadModule: "nv" [ 4.897] (II) Unloading nv [ 4.897] (EE) Failed to load module "nv" (module does not exist, 0) [ 4.897] (II) LoadModule: "vesa" [ 4.898] (II) Loading /usr/lib/xorg/modules/drivers/vesa_drv.so [ 4.898] (II) Module vesa: vendor="X.Org Foundation" [ 4.898] compiled for 1.11.3, module version = 2.3.0 [ 4.898] Module class: X.Org Video Driver [ 4.898] ABI class: X.Org Video Driver, version 11.0 [ 4.898] (II) UnloadModule: "vesa" [ 4.898] (II) Unloading vesa [ 4.898] (II) Failed to load module "vesa" (already loaded, 0) [ 4.898] (II) LoadModule: "fbdev" [ 4.898] (II) Loading /usr/lib/xorg/modules/drivers/fbdev_drv.so [ 4.898] (II) Module fbdev: vendor="X.Org Foundation" [ 4.898] compiled for 1.11.3, module version = 0.4.2 [ 4.898] ABI class: X.Org Video Driver, version 11.0 [ 4.898] (II) UnloadModule: "fbdev" [ 4.898] (II) Unloading fbdev [ 4.899] (II) Failed to load module "fbdev" (already loaded, 0) [ 4.899] (II) NVIDIA dlloader X Driver 295.40 Thu Apr 5 21:38:35 PDT 2012 [ 4.899] (II) NVIDIA Unified Driver for all Supported NVIDIA GPUs [ 4.899] (II) NOUVEAU driver Date: Wed Sep 12 13:42:43 2012 +0200 [ 4.899] (II) NOUVEAU driver for NVIDIA chipset families : [ 4.899] RIVA TNT (NV04) [ 4.899] RIVA TNT2 (NV05) [ 4.899] GeForce 256 (NV10) [ 4.899] GeForce 2 (NV11, NV15) [ 4.899] GeForce 4MX (NV17, NV18) [ 4.899] GeForce 3 (NV20) [ 4.900] GeForce 4Ti (NV25, NV28) [ 4.900] GeForce FX (NV3x) [ 4.900] GeForce 6 (NV4x) [ 4.900] GeForce 7 (G7x) [ 4.900] GeForce 8 (G8x) [ 4.900] GeForce GTX 200 (NVA0) [ 4.900] GeForce GTX 400 (NVC0) [ 4.900] (II) VESA: driver for VESA chipsets: vesa [ 4.900] (II) FBDEV: driver for framebuffer: fbdev [ 4.900] (++) using VT number 7 [ 4.902] (II) Loading sub module "fb" [ 4.902] (II) LoadModule: "fb" [ 4.902] (II) Loading /usr/lib/xorg/modules/libfb.so [ 4.902] (II) Module fb: vendor="X.Org Foundation" [ 4.902] compiled for 1.11.3, module version = 1.0.0 [ 4.902] ABI class: X.Org ANSI C Emulation, version 0.4 [ 4.902] (II) Loading sub module "wfb" [ 4.902] (II) LoadModule: "wfb" [ 4.903] (II) Loading /usr/lib/xorg/modules/libwfb.so [ 4.905] (II) Module wfb: vendor="X.Org Foundation" [ 4.905] compiled for 1.11.3, module version = 1.0.0 [ 4.905] ABI class: X.Org ANSI C Emulation, version 0.4 [ 4.905] (II) Loading sub module "ramdac" [ 4.905] (II) LoadModule: "ramdac" [ 4.905] (II) Module "ramdac" already built-in [ 4.907] (II) Loading /usr/lib/x86_64-linux-gnu/xorg/extra-modules/nvidia_drv.so [ 4.907] (II) Loading /usr/lib/xorg/modules/libwfb.so [ 4.907] (II) Loading /usr/lib/xorg/modules/libfb.so [ 4.912] (WW) Falling back to old probe method for vesa [ 4.912] (WW) Falling back to old probe method for fbdev [ 4.912] (II) Loading sub module "fbdevhw" [ 4.912] (II) LoadModule: "fbdevhw" [ 4.912] (II) Loading /usr/lib/xorg/modules/libfbdevhw.so [ 4.912] (II) Module fbdevhw: vendor="X.Org Foundation" [ 4.912] compiled for 1.11.3, module version = 0.0.2 [ 4.912] ABI class: X.Org Video Driver, version 11.0 [ 4.912] (II) NVIDIA(0): Creating default Display subsection in Screen section "Default Screen Section" for depth/fbbpp 24/32 [ 4.912] (==) NVIDIA(0): Depth 24, (==) framebuffer bpp 32 [ 4.912] (==) NVIDIA(0): RGB weight 888 [ 4.912] (==) NVIDIA(0): Default visual is TrueColor [ 4.912] (==) NVIDIA(0): Using gamma correction (1.0, 1.0, 1.0) [ 4.912] (**) NVIDIA(0): Enabling 2D acceleration [ 5.442] (EE) NVIDIA(0): Failed to initialize the display subsystem for the NVIDIA [ 5.442] (EE) NVIDIA(0): graphics device! [ 5.442] (EE) NVIDIA(0): Failed to get supported display device(s) [ 5.442] (EE) NVIDIA(0): Failed to initialize dac HAL [ 5.442] (II) UnloadModule: "nvidia" [ 5.442] (II) Unloading nvidia [ 5.442] (II) UnloadModule: "wfb" [ 5.442] (II) Unloading wfb [ 5.442] (II) UnloadModule: "fb" [ 5.443] (II) Unloading fb [ 5.443] (EE) Screen(s) found, but none have a usable configuration. [ 5.443] Fatal server error: [ 5.443] no screens found [ 5.443] Please consult the The X.Org Foundation support at http://wiki.x.org for help. [ 5.443] Please also check the log file at "/var/log/Xorg.0.log" for additional information. [ 5.443] [ 5.447] ddxSigGiveUp: Closing log [ 5.447] Server terminated with error (1). Closing log file.

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  • Parallel Classloading Revisited: Fully Concurrent Loading

    - by davidholmes
    Java 7 introduced support for parallel classloading. A description of that project and its goals can be found here: http://openjdk.java.net/groups/core-libs/ClassLoaderProposal.html The solution for parallel classloading was to add to each class loader a ConcurrentHashMap, referenced through a new field, parallelLockMap. This contains a mapping from class names to Objects to use as a classloading lock for that class name. This was then used in the following way: protected Class loadClass(String name, boolean resolve) throws ClassNotFoundException { synchronized (getClassLoadingLock(name)) { // First, check if the class has already been loaded Class c = findLoadedClass(name); if (c == null) { long t0 = System.nanoTime(); try { if (parent != null) { c = parent.loadClass(name, false); } else { c = findBootstrapClassOrNull(name); } } catch (ClassNotFoundException e) { // ClassNotFoundException thrown if class not found // from the non-null parent class loader } if (c == null) { // If still not found, then invoke findClass in order // to find the class. long t1 = System.nanoTime(); c = findClass(name); // this is the defining class loader; record the stats sun.misc.PerfCounter.getParentDelegationTime().addTime(t1 - t0); sun.misc.PerfCounter.getFindClassTime().addElapsedTimeFrom(t1); sun.misc.PerfCounter.getFindClasses().increment(); } } if (resolve) { resolveClass(c); } return c; } } Where getClassLoadingLock simply does: protected Object getClassLoadingLock(String className) { Object lock = this; if (parallelLockMap != null) { Object newLock = new Object(); lock = parallelLockMap.putIfAbsent(className, newLock); if (lock == null) { lock = newLock; } } return lock; } This approach is very inefficient in terms of the space used per map and the number of maps. First, there is a map per-classloader. As per the code above under normal delegation the current classloader creates and acquires a lock for the given class, checks if it is already loaded, then asks its parent to load it; the parent in turn creates another lock in its own map, checks if the class is already loaded and then delegates to its parent and so on till the boot loader is invoked for which there is no map and no lock. So even in the simplest of applications, you will have two maps (in the system and extensions loaders) for every class that has to be loaded transitively from the application's main class. If you knew before hand which loader would actually load the class the locking would only need to be performed in that loader. As it stands the locking is completely unnecessary for all classes loaded by the boot loader. Secondly, once loading has completed and findClass will return the class, the lock and the map entry is completely unnecessary. But as it stands, the lock objects and their associated entries are never removed from the map. It is worth understanding exactly what the locking is intended to achieve, as this will help us understand potential remedies to the above inefficiencies. Given this is the support for parallel classloading, the class loader itself is unlikely to need to guard against concurrent load attempts - and if that were not the case it is likely that the classloader would need a different means to protect itself rather than a lock per class. Ultimately when a class file is located and the class has to be loaded, defineClass is called which calls into the VM - the VM does not require any locking at the Java level and uses its own mutexes for guarding its internal data structures (such as the system dictionary). The classloader locking is primarily needed to address the following situation: if two threads attempt to load the same class, one will initiate the request through the appropriate loader and eventually cause defineClass to be invoked. Meanwhile the second attempt will block trying to acquire the lock. Once the class is loaded the first thread will release the lock, allowing the second to acquire it. The second thread then sees that the class has now been loaded and will return that class. Neither thread can tell which did the loading and they both continue successfully. Consider if no lock was acquired in the classloader. Both threads will eventually locate the file for the class, read in the bytecodes and call defineClass to actually load the class. In this case the first to call defineClass will succeed, while the second will encounter an exception due to an attempted redefinition of an existing class. It is solely for this error condition that the lock has to be used. (Note that parallel capable classloaders should not need to be doing old deadlock-avoidance tricks like doing a wait() on the lock object\!). There are a number of obvious things we can try to solve this problem and they basically take three forms: Remove the need for locking. This might be achieved by having a new version of defineClass which acts like defineClassIfNotPresent - simply returning an existing Class rather than triggering an exception. Increase the coarseness of locking to reduce the number of lock objects and/or maps. For example, using a single shared lockMap instead of a per-loader lockMap. Reduce the lifetime of lock objects so that entries are removed from the map when no longer needed (eg remove after loading, use weak references to the lock objects and cleanup the map periodically). There are pros and cons to each of these approaches. Unfortunately a significant "con" is that the API introduced in Java 7 to support parallel classloading has essentially mandated that these locks do in fact exist, and they are accessible to the application code (indirectly through the classloader if it exposes them - which a custom loader might do - and regardless they are accessible to custom classloaders). So while we can reason that we could do parallel classloading with no locking, we can not implement this without breaking the specification for parallel classloading that was put in place for Java 7. Similarly we might reason that we can remove a mapping (and the lock object) because the class is already loaded, but this would again violate the specification because it can be reasoned that the following assertion should hold true: Object lock1 = loader.getClassLoadingLock(name); loader.loadClass(name); Object lock2 = loader.getClassLoadingLock(name); assert lock1 == lock2; Without modifying the specification, or at least doing some creative wordsmithing on it, options 1 and 3 are precluded. Even then there are caveats, for example if findLoadedClass is not atomic with respect to defineClass, then you can have concurrent calls to findLoadedClass from different threads and that could be expensive (this is also an argument against moving findLoadedClass outside the locked region - it may speed up the common case where the class is already loaded, but the cost of re-executing after acquiring the lock could be prohibitive. Even option 2 might need some wordsmithing on the specification because the specification for getClassLoadingLock states "returns a dedicated object associated with the specified class name". The question is, what does "dedicated" mean here? Does it mean unique in the sense that the returned object is only associated with the given class in the current loader? Or can the object actually guard loading of multiple classes, possibly across different class loaders? So it seems that changing the specification will be inevitable if we wish to do something here. In which case lets go for something that more cleanly defines what we want to be doing: fully concurrent class-loading. Note: defineClassIfNotPresent is already implemented in the VM as find_or_define_class. It is only used if the AllowParallelDefineClass flag is set. This gives us an easy hook into existing VM mechanics. Proposal: Fully Concurrent ClassLoaders The proposal is that we expand on the notion of a parallel capable class loader and define a "fully concurrent parallel capable class loader" or fully concurrent loader, for short. A fully concurrent loader uses no synchronization in loadClass and the VM uses the "parallel define class" mechanism. For a fully concurrent loader getClassLoadingLock() can return null (or perhaps not - it doesn't matter as we won't use the result anyway). At present we have not made any changes to this method. All the parallel capable JDK classloaders become fully concurrent loaders. This doesn't require any code re-design as none of the mechanisms implemented rely on the per-name locking provided by the parallelLockMap. This seems to give us a path to remove all locking at the Java level during classloading, while retaining full compatibility with Java 7 parallel capable loaders. Fully concurrent loaders will still encounter the performance penalty associated with concurrent attempts to find and prepare a class's bytecode for definition by the VM. What this penalty is depends on the number of concurrent load attempts possible (a function of the number of threads and the application logic, and dependent on the number of processors), and the costs associated with finding and preparing the bytecodes. This obviously has to be measured across a range of applications. Preliminary webrevs: http://cr.openjdk.java.net/~dholmes/concurrent-loaders/webrev.hotspot/ http://cr.openjdk.java.net/~dholmes/concurrent-loaders/webrev.jdk/ Please direct all comments to the mailing list [email protected].

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  • Farseer tutorial for the absolute beginners

    - by Bil Simser
    This post is inspired (and somewhat a direct copy) of a couple of posts Emanuele Feronato wrote back in 2009 about Box2D (his tutorial was ActionScript 3 based for Box2D, this is C# XNA for the Farseer Physics Engine). Here’s what we’re building: What is Farseer The Farseer Physics Engine is a collision detection system with realistic physics responses to help you easily create simple hobby games or complex simulation systems. Farseer was built as a .NET version of Box2D (based on the Box2D.XNA port of Box2D). While the constructs and syntax has changed over the years, the principles remain the same. This tutorial will walk you through exactly what Emanuele create for Flash but we’ll be doing it using C#, XNA and the Windows Phone platform. The first step is to download the library from its home on CodePlex. If you have NuGet installed, you can install the library itself using the NuGet package that but we’ll also be using some code from the Samples source that can only be obtained by downloading the library. Once you download and unpacked the zip file into a folder and open the solution, this is what you will get: The Samples XNA WP7 project (and content) have all the demos for Farseer. There’s a wealth of info here and great examples to look at to learn. The Farseer Physics XNA WP7 project contains the core libraries that do all the work. DebugView XNA contains an XNA-ready class to let you view debug data and information in the game draw loop (which you can copy into your project or build the source and reference the assembly). The downloaded version has to be compiled as it’s only available in source format so you can do that now if you want (open the solution file and rebuild everything). If you’re using the NuGet package you can just install that. We only need the core library and we’ll be copying in some code from the samples later. Your first Farseer experiment Start Visual Studio and create a new project using the Windows Phone template can call it whatever you want. It’s time to edit Game1.cs 1 public class Game1 : Game 2 { 3 private readonly GraphicsDeviceManager _graphics; 4 private DebugViewXNA _debugView; 5 private Body _floor; 6 private SpriteBatch _spriteBatch; 7 private float _timer; 8 private World _world; 9 10 public Game1() 11 { 12 _graphics = new GraphicsDeviceManager(this) 13 { 14 PreferredBackBufferHeight = 800, 15 PreferredBackBufferWidth = 480, 16 IsFullScreen = true 17 }; 18 19 Content.RootDirectory = "Content"; 20 21 // Frame rate is 30 fps by default for Windows Phone. 22 TargetElapsedTime = TimeSpan.FromTicks(333333); 23 24 // Extend battery life under lock. 25 InactiveSleepTime = TimeSpan.FromSeconds(1); 26 } 27 28 protected override void LoadContent() 29 { 30 // Create a new SpriteBatch, which can be used to draw textures. 31 _spriteBatch = new SpriteBatch(_graphics.GraphicsDevice); 32 33 // Load our font (DebugViewXNA needs it for the DebugPanel) 34 Content.Load<SpriteFont>("font"); 35 36 // Create our World with a gravity of 10 vertical units 37 if (_world == null) 38 { 39 _world = new World(Vector2.UnitY*10); 40 } 41 else 42 { 43 _world.Clear(); 44 } 45 46 if (_debugView == null) 47 { 48 _debugView = new DebugViewXNA(_world); 49 50 // default is shape, controller, joints 51 // we just want shapes to display 52 _debugView.RemoveFlags(DebugViewFlags.Controllers); 53 _debugView.RemoveFlags(DebugViewFlags.Joint); 54 55 _debugView.LoadContent(GraphicsDevice, Content); 56 } 57 58 // Create and position our floor 59 _floor = BodyFactory.CreateRectangle( 60 _world, 61 ConvertUnits.ToSimUnits(480), 62 ConvertUnits.ToSimUnits(50), 63 10f); 64 _floor.Position = ConvertUnits.ToSimUnits(240, 775); 65 _floor.IsStatic = true; 66 _floor.Restitution = 0.2f; 67 _floor.Friction = 0.2f; 68 } 69 70 protected override void Update(GameTime gameTime) 71 { 72 // Allows the game to exit 73 if (GamePad.GetState(PlayerIndex.One).Buttons.Back == ButtonState.Pressed) 74 Exit(); 75 76 // Create a random box every second 77 _timer += (float) gameTime.ElapsedGameTime.TotalSeconds; 78 if (_timer >= 1.0f) 79 { 80 // Reset our timer 81 _timer = 0f; 82 83 // Determine a random size for each box 84 var random = new Random(); 85 var width = random.Next(20, 100); 86 var height = random.Next(20, 100); 87 88 // Create it and store the size in the user data 89 var box = BodyFactory.CreateRectangle( 90 _world, 91 ConvertUnits.ToSimUnits(width), 92 ConvertUnits.ToSimUnits(height), 93 10f, 94 new Point(width, height)); 95 96 box.BodyType = BodyType.Dynamic; 97 box.Restitution = 0.2f; 98 box.Friction = 0.2f; 99 100 // Randomly pick a location along the top to drop it from 101 box.Position = ConvertUnits.ToSimUnits(random.Next(50, 400), 0); 102 } 103 104 // Advance all the elements in the world 105 _world.Step(Math.Min((float) gameTime.ElapsedGameTime.TotalMilliseconds*0.001f, (1f/30f))); 106 107 // Clean up any boxes that have fallen offscreen 108 foreach (var box in from box in _world.BodyList 109 let pos = ConvertUnits.ToDisplayUnits(box.Position) 110 where pos.Y > _graphics.GraphicsDevice.Viewport.Height 111 select box) 112 { 113 _world.RemoveBody(box); 114 } 115 116 base.Update(gameTime); 117 } 118 119 protected override void Draw(GameTime gameTime) 120 { 121 GraphicsDevice.Clear(Color.FromNonPremultiplied(51, 51, 51, 255)); 122 123 _spriteBatch.Begin(); 124 125 var projection = Matrix.CreateOrthographicOffCenter( 126 0f, 127 ConvertUnits.ToSimUnits(_graphics.GraphicsDevice.Viewport.Width), 128 ConvertUnits.ToSimUnits(_graphics.GraphicsDevice.Viewport.Height), 0f, 0f, 129 1f); 130 _debugView.RenderDebugData(ref projection); 131 132 _spriteBatch.End(); 133 134 base.Draw(gameTime); 135 } 136 } 137 Lines 4: Declare the debug view we’ll use for rendering (more on that later). Lines 8: Declare _world variable of type class World. World is the main object to interact with the Farseer engine. It stores all the joints and bodies, and is responsible for stepping through the simulation. Lines 12-17: Create the graphics device we’ll be rendering on. This is an XNA component and we’re just setting it to be the same size as the phone and toggling it to be full screen (no system tray). Lines 34: We create a SpriteFont here by adding it to the project. It’s called “font” because that’s what the DebugView uses but you can name it whatever you want (and if you’re not using DebugView for your production app you might have several fonts). Lines 37-44: We create the physics environment that Farseer uses to contain all the objects by specifying it here. We’re using Vector2.UnitY*10 to represent the gravity to be used in the environment. In other words, 10 units going in a downward motion. Lines 46-56: We create the DebugViewXNA here. This is copied from the […] from the code you downloaded and provides the ability to render all entities onto the screen. In a production release you’ll be doing the rendering yourself of each object but we cheat a bit for the demo and let the DebugView do it for us. The other thing it can provide is to render out a panel of debugging information while the simulation is going on. This is useful in tracking down objects, figuring out how something works, or just keeping track of what’s in the engine. Lines 49-67: Here we create a rigid body (Farseer only supports rigid bodies) to represent the floor that we’ll drop objects onto. We create it by using one of the Farseer factories and specifying the width and height. The ConvertUnits class is copied from the samples code as-is and lets us toggle between display units (pixels) and simulation units (usually metres). We’re creating a floor that’s 480 pixels wide and 50 pixels high (converting them to SimUnits for the engine to understand). We also position it near the bottom of the screen. Values are in metres and when specifying values they refer to the centre of the body object. Lines 77-78: The game Update method fires 30 times a second, too fast to be creating objects this quickly. So we use a variable to track the elapsed seconds since the last update, accumulate that value, then create a new box to drop when 1 second has passed. Lines 89-94: We create a box the same way we created our floor (coming up with a random width and height for the box). Lines 96-101: We set the box to be Dynamic (rather than Static like the floor object) and position it somewhere along the top of the screen. And now you created the world. Gravity does the rest and the boxes fall to the ground. Here’s the result: Farseer Physics Engine Demo using XNA Lines 105: We must update the world at every frame. We do this with the Step method which takes in the time interval. [more] Lines 108-114: Body objects are added to the world but never automatically removed (because Farseer doesn’t know about the display world, it has no idea if an item is on the screen or not). Here we just loop through all the entities and anything that’s dropped off the screen (below the bottom) gets removed from the World. This keeps our entity count down (the simulation never has more than 30 or 40 objects in the world no matter how long you run it for). Too many entities and the app will grind to a halt. Lines 125-130: Farseer knows nothing about the UI so that’s entirely up to you as to how to draw things. Farseer is just tracking the objects and moving them around using the physics engine and it’s rules. You’ll still use XNA to draw items (using the SpriteBatch.Draw method) so you can load up your usual textures and draw items and pirates and dancing zombies all over the screen. Instead in this demo we’re going to cheat a little. In the sample code for Farseer you can download there’s a project called DebugView XNA. This project contains the DebugViewXNA class which just handles iterating through all the bodies in the world and drawing the shapes. So we call the RenderDebugData method here of that class to draw everything correctly. In the case of this demo, we just want to draw Shapes so take a look at the source code for the DebugViewXNA class as to how it extracts all the vertices for the shapes created (in this case simple boxes) and draws them. You’ll learn a *lot* about how Farseer works just by looking at this class. That’s it, that’s all. Simple huh? Hope you enjoy the code and library. Physics is hard and requires some math skills to really grok. The Farseer Physics Engine makes it pretty easy to get up and running and start building games. In future posts we’ll get more in-depth with things you can do with the engine so this is just the beginning. Enjoy!

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  • StreamInsight 2.1, meet LINQ

    - by Roman Schindlauer
    Someone recently called LINQ “magic” in my hearing. I leapt to LINQ’s defense immediately. Turns out some people don’t realize “magic” is can be a pejorative term. I thought LINQ needed demystification. Here’s your best demystification resource: http://blogs.msdn.com/b/mattwar/archive/2008/11/18/linq-links.aspx. I won’t repeat much of what Matt Warren says in his excellent series, but will talk about some core ideas and how they affect the 2.1 release of StreamInsight. Let’s tell the story of a LINQ query. Compile time It begins with some code: IQueryable<Product> products = ...; var query = from p in products             where p.Name == "Widget"             select p.ProductID; foreach (int id in query) {     ... When the code is compiled, the C# compiler (among other things) de-sugars the query expression (see C# spec section 7.16): ... var query = products.Where(p => p.Name == "Widget").Select(p => p.ProductID); ... Overload resolution subsequently binds the Queryable.Where<Product> and Queryable.Select<Product, int> extension methods (see C# spec sections 7.5 and 7.6.5). After overload resolution, the compiler knows something interesting about the anonymous functions (lambda syntax) in the de-sugared code: they must be converted to expression trees, i.e.,“an object structure that represents the structure of the anonymous function itself” (see C# spec section 6.5). The conversion is equivalent to the following rewrite: ... var prm1 = Expression.Parameter(typeof(Product), "p"); var prm2 = Expression.Parameter(typeof(Product), "p"); var query = Queryable.Select<Product, int>(     Queryable.Where<Product>(         products,         Expression.Lambda<Func<Product, bool>>(Expression.Property(prm1, "Name"), prm1)),         Expression.Lambda<Func<Product, int>>(Expression.Property(prm2, "ProductID"), prm2)); ... If the “products” expression had type IEnumerable<Product>, the compiler would have chosen the Enumerable.Where and Enumerable.Select extension methods instead, in which case the anonymous functions would have been converted to delegates. At this point, we’ve reduced the LINQ query to familiar code that will compile in C# 2.0. (Note that I’m using C# snippets to illustrate transformations that occur in the compiler, not to suggest a viable compiler design!) Runtime When the above program is executed, the Queryable.Where method is invoked. It takes two arguments. The first is an IQueryable<> instance that exposes an Expression property and a Provider property. The second is an expression tree. The Queryable.Where method implementation looks something like this: public static IQueryable<T> Where<T>(this IQueryable<T> source, Expression<Func<T, bool>> predicate) {     return source.Provider.CreateQuery<T>(     Expression.Call(this method, source.Expression, Expression.Quote(predicate))); } Notice that the method is really just composing a new expression tree that calls itself with arguments derived from the source and predicate arguments. Also notice that the query object returned from the method is associated with the same provider as the source query. By invoking operator methods, we’re constructing an expression tree that describes a query. Interestingly, the compiler and operator methods are colluding to construct a query expression tree. The important takeaway is that expression trees are built in one of two ways: (1) by the compiler when it sees an anonymous function that needs to be converted to an expression tree, and; (2) by a query operator method that constructs a new queryable object with an expression tree rooted in a call to the operator method (self-referential). Next we hit the foreach block. At this point, the power of LINQ queries becomes apparent. The provider is able to determine how the query expression tree is evaluated! The code that began our story was intentionally vague about the definition of the “products” collection. Maybe it is a queryable in-memory collection of products: var products = new[]     { new Product { Name = "Widget", ProductID = 1 } }.AsQueryable(); The in-memory LINQ provider works by rewriting Queryable method calls to Enumerable method calls in the query expression tree. It then compiles the expression tree and evaluates it. It should be mentioned that the provider does not blindly rewrite all Queryable calls. It only rewrites a call when its arguments have been rewritten in a way that introduces a type mismatch, e.g. the first argument to Queryable.Where<Product> being rewritten as an expression of type IEnumerable<Product> from IQueryable<Product>. The type mismatch is triggered initially by a “leaf” expression like the one associated with the AsQueryable query: when the provider recognizes one of its own leaf expressions, it replaces the expression with the original IEnumerable<> constant expression. I like to think of this rewrite process as “type irritation” because the rewritten leaf expression is like a foreign body that triggers an immune response (further rewrites) in the tree. The technique ensures that only those portions of the expression tree constructed by a particular provider are rewritten by that provider: no type irritation, no rewrite. Let’s consider the behavior of an alternative LINQ provider. If “products” is a collection created by a LINQ to SQL provider: var products = new NorthwindDataContext().Products; the provider rewrites the expression tree as a SQL query that is then evaluated by your favorite RDBMS. The predicate may ultimately be evaluated using an index! In this example, the expression associated with the Products property is the “leaf” expression. StreamInsight 2.1 For the in-memory LINQ to Objects provider, a leaf is an in-memory collection. For LINQ to SQL, a leaf is a table or view. When defining a “process” in StreamInsight 2.1, what is a leaf? To StreamInsight a leaf is logic: an adapter, a sequence, or even a query targeting an entirely different LINQ provider! How do we represent the logic? Remember that a standing query may outlive the client that provisioned it. A reference to a sequence object in the client application is therefore not terribly useful. But if we instead represent the code constructing the sequence as an expression, we can host the sequence in the server: using (var server = Server.Connect(...)) {     var app = server.Applications["my application"];     var source = app.DefineObservable(() => Observable.Range(0, 10, Scheduler.NewThread));     var query = from i in source where i % 2 == 0 select i; } Example 1: defining a source and composing a query Let’s look in more detail at what’s happening in example 1. We first connect to the remote server and retrieve an existing app. Next, we define a simple Reactive sequence using the Observable.Range method. Notice that the call to the Range method is in the body of an anonymous function. This is important because it means the source sequence definition is in the form of an expression, rather than simply an opaque reference to an IObservable<int> object. The variation in Example 2 fails. Although it looks similar, the sequence is now a reference to an in-memory observable collection: var local = Observable.Range(0, 10, Scheduler.NewThread); var source = app.DefineObservable(() => local); // can’t serialize ‘local’! Example 2: error referencing unserializable local object The Define* methods support definitions of operator tree leaves that target the StreamInsight server. These methods all have the same basic structure. The definition argument is a lambda expression taking between 0 and 16 arguments and returning a source or sink. The method returns a proxy for the source or sink that can then be used for the usual style of LINQ query composition. The “define” methods exploit the compile-time C# feature that converts anonymous functions into translatable expression trees! Query composition exploits the runtime pattern that allows expression trees to be constructed by operators taking queryable and expression (Expression<>) arguments. The practical upshot: once you’ve Defined a source, you can compose LINQ queries in the familiar way using query expressions and operator combinators. Notably, queries can be composed using pull-sequences (LINQ to Objects IQueryable<> inputs), push sequences (Reactive IQbservable<> inputs), and temporal sequences (StreamInsight IQStreamable<> inputs). You can even construct processes that span these three domains using “bridge” method overloads (ToEnumerable, ToObservable and To*Streamable). Finally, the targeted rewrite via type irritation pattern is used to ensure that StreamInsight computations can leverage other LINQ providers as well. Consider the following example (this example depends on Interactive Extensions): var source = app.DefineEnumerable((int id) =>     EnumerableEx.Using(() =>         new NorthwindDataContext(), context =>             from p in context.Products             where p.ProductID == id             select p.ProductName)); Within the definition, StreamInsight has no reason to suspect that it ‘owns’ the Queryable.Where and Queryable.Select calls, and it can therefore defer to LINQ to SQL! Let’s use this source in the context of a StreamInsight process: var sink = app.DefineObserver(() => Observer.Create<string>(Console.WriteLine)); var query = from name in source(1).ToObservable()             where name == "Widget"             select name; using (query.Bind(sink).Run("process")) {     ... } When we run the binding, the source portion which filters on product ID and projects the product name is evaluated by SQL Server. Outside of the definition, responsibility for evaluation shifts to the StreamInsight server where we create a bridge to the Reactive Framework (using ToObservable) and evaluate an additional predicate. It’s incredibly easy to define computations that span multiple domains using these new features in StreamInsight 2.1! Regards, The StreamInsight Team

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  • Building Enterprise Smartphone App &ndash; Part 4: Application Development Considerations

    - by Tim Murphy
    This is the final part in a series of posts based on a talk I gave recently at the Chicago Information Technology Architects Group.  Feel free to leave feedback. Application Development Considerations Now we get to the actual building of your solutions.  What are the skills and resources that will be needed in order to develop a smartphone application in the enterprise? Language Knowledge One of the first things you need to consider when you are deciding which platform language do you either have the most in house skill base or can you easily acquire.  If you already have developers who know Java or C# you may want to use either Android or Windows Phone.  You should also take into consideration the market availability of developers.  If your key developer leaves how easy is it to find a knowledgeable replacement? A second consideration when it comes to programming languages is the qualities exposed by the languages of a particular platform.  How well does that development language and its associated frameworks support things like security and access to the features of the smartphone hardware?  This will play into your overall cost of ownership if you have to create this infrastructure on your own. Manage Limited Resources Everything is limited on a smartphone: battery, memory, processing power, network bandwidth.  When developing your applications you will have to keep your footprint as small as possible in every way.  This means not running unnecessary processes in the background that will drain the battery or pulling more data over the airwaves than you have to.  You also want to keep your on device in as compact a format as possible. Mobile Design Patterns There are a number of design patterns that have either come to life because of smartphone development or have been adapted for this use.  The main pattern in the Windows Phone environment is the MVVM (Model-View-View-Model).  This is great for overall application structure and separation of concerns.  The fun part is trying to keep that separation as pure as possible.  Many of the other patterns may or may not have strict definitions, but some that you need to be concerned with are push notification, asynchronous communication and offline data storage. Real estate is limited on smartphones and even tablets. You are also limited in the type of controls that can be represented in the UI. This means rethinking how you modularize your application. Typing is also much harder to do so you want to reduce this as much as possible.  This leads to UI patterns.  While not what we would traditionally think of as design patterns the guidance each platform has for UI design is critical to the success of your application.  If user find the application difficult navigate they will not use it. Development Process Because of the differences in development tools required, test devices and certification and deployment processes your teams will need to learn new way of working together.  This will include the need to integrate service contracts of back-end systems with mobile applications.  You will also want to make sure that you present consistency across different access points to corporate data.  Your web site may have more functionality than your smartphone application, but it should have a consistent core set of functionality.  This all requires greater communication between sub-teams of your developers. Testing Process Testing of smartphone apps has a lot more to do with what happens when you lose connectivity or if the user navigates away from your application. There are a lot more opportunities for the user or the device to perform disruptive acts.  This should be your main testing concentration aside from the main business requirements.  You will need to do things like setting the phone to airplane mode and seeing what the application does in order to weed out any gaps in your handling communication interruptions. Need For Outside Experts Since this is a development area that is new to most companies the need for experts is a lot greater. Whether these are consultants, vendor representatives or just development community forums you will need to establish expert contacts. Nothing is more dangerous for your project timelines than a lack of knowledge.  Make sure you know who to call to avoid lengthy delays in your project because of knowledge gaps. Security Security has to be a major concern for enterprise applications. You aren't dealing with just someone's game standings. You are dealing with a companies intellectual property and competitive advantage. As such you need to start by limiting access to the application itself.  Once the user is in the app you need to ensure that the data is secure at all times.  This includes both local storage and across the wire.  This means if a platform doesn’t natively support encryption for these functions you will need to find alternatives to secure your data.  You also need to keep secret (encryption) keys obfuscated or locked away outside of the application. People can disassemble the code otherwise and break your encryption. Offline Capabilities As we discussed earlier one your biggest concerns is not having connectivity.  Because of this a good portion of your code may be dedicated to handling loss of connection and reconnection situations.  What do you do if you lose the network?  Back up all your transactions and store of any supporting data so that operations can continue off line. In order to support this you will need to determine the available flat file or local data base capabilities of the platform.  Any failed transactions will need to support a retry mechanism whether it is automatic or user initiated.  This also includes your services since they will need to be able to roll back partially completed transactions.  What ever you do, don’t ignore this area when you are designing your system. Deployment Each platform has different deployment capabilities. Some are more suited to enterprise situations than others. Apple's approach is probably the most mature at the moment. Prior to the current generation of smartphone platforms it would have been Windows CE. Windows Phone 7 has the limitation that the app has to be distributed through the same network as public facing applications. You mark them as private which means that they are only accessible by a direct URL. Unfortunately this does not make them undiscoverable (although it is very difficult). This will change with Windows Phone 8 where companies will be able to certify their own applications and distribute them.  Given this Windows Phone applications need to be more diligent with application access in order to keep them restricted to the company's employees. My understanding of the Android deployment schemes is that it is much less standardized then either iOS or Windows Phone. Someone would have to confirm or deny that for me though since I have not yet put the time into researching this platform further. Given my limited exposure to the iOS and Android platforms I have not been able to confirm this, but there are varying degrees of user involvement to install and keep applications updated. At one extreme the user just goes to a website to do the install and in other case they may need to download files and perform steps to install them. Future Bluetooth Today we use Bluetooth for keyboards, mice and headsets.  In the future it could be used to interrogate car computers or manufacturing systems or possibly retail machines by service techs.  This would open smartphones to greater use as a almost a Star Trek Tricorder.  You would get you all your data as well as being able to use it as a universal remote for just about any device or machine. Better corporation controlled deployment At least in the Windows Phone world the upcoming release of Windows Phone 8 will include a private certification and deployment option that is currently not available with Windows Phone 7 (Mango). We currently have to run the apps through the Marketplace certification process and use a targeted distribution method. Platform independent approaches HTML5 and JavaScript with Web Service has become a popular topic lately for not only creating flexible web site, but also creating cross platform mobile applications.  I’m not yet convinced that this lowest common denominator approach is viable in most cases, but it does have it’s place and seems to be growing.  Be sure to keep an eye on it. Summary From my perspective enterprise smartphone applications can offer a great competitive advantage to many companies.  They are not cheap to build and should be approached cautiously.  Understand the factors I have outlined in this series, do you due diligence and see if there is a portion of your business that can benefit from the mobile experience. del.icio.us Tags: Architecture,Smartphones,Windows Phone,iOS,Android

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