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  • Analysing SQLBits Feedback

    - by jamiet
    Earlier this week I received all the feedback that people offered on my session at SQLBits 7 in York – “SSIS Dataflow Performance Tuning” (the video is available online if you wish to see it). As you may have gathered from previous posts on this blog and my less-SQLy-focused Wordpress blog I am a big fan of collecting and tracking both personal and public data and session feedback lends itself very well to tracking because it is quantitative rather than qualitative; by that I mean attendees are invited to provide marks out of ten rather than (or, in the case of SQLBits, as well as) written comments. The SQLBits feedback is also useful because they use a consistent format – the same questions are asked each time – this means it is particularly easy to to track whether the scores that people give are trending up or down. I suspect that somewhere the SQLBits organisers have a big Analysis Services cube (ok, perhaps its an Excel pivot table) that allows them to analyse these scores per conference, speaker, track etc.… and there’s no reason that we as session speakers cannot do the same thing. To that end I have started to store my feedback in an Excel spreadsheet of my own which in the interests of transparency is available for public viewing (only a web browser required) on SkyDrive at http://cid-550f681dad532637.office.live.com/view.aspx/Public/Misc/Personal%20SQLBits%20Session%20Feedback.xlsx. I have used a pivot table to aggregate all that feedback and here is a screenshot: I am hereby making a public plea to the SQLBits organisers (on the off-chance that they are reading) to please continue to keep the feedback format consistent in the future and I encourage them to publish all of the feedback in an anonymised form. I would also encourage anyone doing conference speaking to track their conference feedback in the same way that I am doing so that you get an insight into whether or not you are improving over time. It is not difficult to setup and maintaining it as you do more sessions takes very little effort. Storing feedback data like this leads me to wider thoughts about well-known conventions and data format standardisation. Let’s imagine a utopia where there were a standard set of questions for capturing session feedback that were leveraged at every conference regardless of subject matter, location or culture; that would give rise to immense cross-conference and cross-discipline analysis – the data analyst in me goes giddy at the thought of it. It is scenarios like this that drive my interest both in data formats such as iCalendar, microformats and RDF, and in emerging movements such as the semantic web and linked data, all things which I have written about in the past. I don’t know whether we will ever reach the stage where every piece of data has structured, descriptive metadata associated with it but I live in hope. @Jamiet

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  • Getting a virus is *very* annoying

    - by bconlon
    I spent most of yesterday removing an annoying virus from my PC. I feel slightly foolish for getting one in the first place, but after so many years I guess I was always going to eventually succumb. I was also a little surprised at the failure of various tools at removing it. The virus would redirect the browser to websites including ‘licosearch’, ‘hugosearch’ and ‘facebook’, and the disk would be thrashing away infecting dlls in some way. I had the full up to date version of McAfee installed. This identified that there was an issue in some dlls on the system and was able to ‘fix’ them. But they kept getting re-infected. So I installed Microsoft Security Essentials and this too was able to identify and ‘fix’ the infected dlls. The system scans take forever and I really expected better results. I also tried Malwarebytes, Hitman Pro, AVG and Sophos to no avail. Eventually I thought I’d investigate myself. It turned out that on reboot, the virus would start 3 instances of Firefox.exe which I’m guessing would do bad things including infecting as many dlls on the system as possible. I removed Firefox and the virus cleverly then launched 3 instances of Chrome! So I uninstalled Chrome and yes, it then started to launch 3 instances of iexplore.exe. If I’m honest, by this stage I was just seeing if it would be able to use any of the browsers! As it was starting these on reboot, I looked in my User Startup folder and there was a <randomly named>.exe and several log files. I deleted these and rebooted. When I looked they had been recreated. So I then looked in the registry Run and RunOnce entries: HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run. Sure enough there were entries to run a file in C:\Program Files\<random name folder>\<random name file>.exe. I deleted this and rebooted and it was fixed. I also looked in the event log and found a warning that Winlogon had failed to start the file C:\Program Files\<random name folder>\<random name file>.exe So I also checked HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon and this entry had also been changed. Finally I ran a full system scan to clean up any infected dlls. I hope it’s gone for good!  #

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  • AWS EC2 Oracle RDB - Storing and managing my data

    - by llaszews
    When create an Oracle Database on the Amazon cloud you will need to store you database files somewhere on the EC2 cloud. There are basically three places where database files can be stored: 1. Local drive - This is the local drive that is part of the virtual server EC2 instance. 2. Elastic Block Storage (EBS) - Network attached storage that appears as a local drive. 3. Simple Storage Server (S3) - 'Storage for the Internet'. S3 is not high speed and intended for store static document type files. S3 can also be used for storing static web page files. Local drives are ephemeral so not appropriate to be used as a database storage device. The leaves EBS which is the best place to store database files. EBS volumes appear as local disk drives. They are actually network-attached to an Amazon EC2 instance. In addition, EBS persists independently from the running life of a single Amazon EC2 instance. If you use an EBS backed instance for your database data, it will remain available after reboot but not after terminate. In many cases you would not need to terminate your instance but only stop it, which is equivalent of shutdown. In order to save your database data before you terminate an instance, you can snapshot the EBS to S3. Using EBS as a data store you can move your Oracle data files from one instance to another. This allows you to move your database from one region or or zone to another. Unfortunately, to scale out your Oracle RDS on AWS you can not have read only replicas. This is only possible with the other Oracle relational database - MySQL. The free micro instances use EBS as its storage. This is a very good white paper that has more details: AWS Storage Options This white paper also discusses: SQS, SimpleDB, and Amazon RDS in the context of storage devices. However, these are not storage devices you would use to store an Oracle database. This slide deck discusses a lot of information that is in the white paper: AWS Storage Options slideshow

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  • Ubuntu 12.04 updates fail recently - Please help

    - by user74152
    I upgraded Ubuntu 11.10 to 12.04 LTS immediately after its release (april 2012). Since then updates (new kernels and others) succeeded regularly, but recently, suddenly, updates fail consistently. What causes the problem and how can it be solved? Terminal information after the last update attempt: ariel@ariel-MS-7592:~$ sudo apt-get upgrade Reading package lists... Done Building dependency tree Reading state information... Done 0 upgraded, 0 newly installed, 0 to remove and 0 not upgraded. 3 not fully installed or removed. After this operation, 0 B of additional disk space will be used. Do you want to continue [Y/n]? y Setting up linux-image-3.2.0-26-generic (3.2.0-26.41) ... Running depmod. update-initramfs: deferring update (hook will be called later) Examining /etc/kernel/postinst.d. run-parts: executing /etc/kernel/postinst.d/dkms 3.2.0-26-generic /boot/vmlinuz-3.2.0-26-generic run-parts: executing /etc/kernel/postinst.d/initramfs-tools 3.2.0-26-generic /boot/vmlinuz-3.2.0-26-generic update-initramfs: Generating /boot/initrd.img-3.2.0-26-generic run-parts: executing /etc/kernel/postinst.d/pm-utils 3.2.0-26-generic /boot/vmlinuz-3.2.0-26-generic run-parts: executing /etc/kernel/postinst.d/update-notifier 3.2.0-26-generic /boot/vmlinuz-3.2.0-26-generic run-parts: executing /etc/kernel/postinst.d/zz-update-grub 3.2.0-26-generic /boot/vmlinuz-3.2.0-26-generic /usr/sbin/grub-mkconfig: 11: /etc/default/grub: splash”: not found run-parts: /etc/kernel/postinst.d/zz-update-grub exited with return code 127 Failed to process /etc/kernel/postinst.d at /var/lib/dpkg/info/linux-image-3.2.0-26-generic.postinst line 1010. dpkg: error processing linux-image-3.2.0-26-generic (--configure): subprocess installed post-installation script returned error exit status 2 No apport report written because MaxReports is reached already dpkg: dependency problems prevent configuration of linux-image-generic: linux-image-generic depends on linux-image-3.2.0-26-generic; however: Package linux-image-3.2.0-26-generic is not configured yet. dpkg: error processing linux-image-generic (--configure): dependency problems - leaving unconfigured dpkg: dependency problems prevent configuration of linux-generic: linux-generic depends on linux-image-generic (= 3.2.0.26.28); however: Package linux-image-generic is not configured yet. dpkg: error processing linux-generic (--configure): dependency problems - leaving unconfiguredNo apport report written because MaxReports is reached already No apport report written because MaxReports is reached already Errors were encountered while processing: linux-image-3.2.0-26-generic linux-image-generic linux-generic E: Sub-process /usr/bin/dpkg returned an error code (1)

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  • S11 launched

    - by unixman
    Now that Oracle Solaris 11 is out, its time to do 2 things -- 1) Its time to see what's in it, what's new and why its important, and then assess why it might make sense to begin evaluating it for your needs and 2) Its time to acknowledge, give thanks to and congratulate all the R&D personnel, architects, engineers, designers and testers who've put in so much effort and energy into helping make Solaris 11 (and SunOS 5.11) what it has become -- starting way back circa 2004 and, more importantly, culminating in the recent years and months -- staying focused on the execution, unwavering in the face of various challenges. For #1 above, here are a few good things to get going with - Watch the product launch replay - Visit the Solaris 11 Spotlight section on oracle.com - Get comfortable through introductory videos and detailed "how-to" guides (ex: how to create and publish IPS packages), white papers on the new default root file system, ZFS, and reap the benefits brought on by the fundamental shift in easing the administration experience - Look at the next level of software lifecycle management that is enabled by technologies such as Automated Installer and Image Packaging System -- that dramatically address patch management-related challenges - Understand how we continue to innovate in areas of service intelligence, reliability and availability - Start to evaluate enhancements in virtualization capabilities -- whether influenced by the need to consolidate or motivated by the need to have increased service mobility across physical systems, leveraging hardware-level abstractions - Gain more control over your network-centric services through enhancements in network resource management, observability and I/O performance - Look beyond your existing infrastructure with confidence that you can re-host and transition to newer systems with the use of Solaris 10 zones running on top of Solaris 11 - Relish in the fact that you can do all this, get your data to be secure and encrypted and more, on both, SPARC and x86-based systems. - Stay informed by keeping an eye on relevant blogs, which we've begun turning up recently. - Go through a hands-on lab - Sign up to take a class or just opt to watch various videos to begin to raise your comfort level with these technologies For #2 above -- There are many ways to do that. One way is to just say "thanks" with an email, a post, or a simple card,  similar to this one seen at a Barnes and Noble store recently.  The front of the card is followed by what's inside... and as the saying goes, now more then ever "it's what's inside that counts" And here's the inside of the card: So, what are you waiting for ? Go download and try it out, and please let us know what you think of it!

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  • PASS Summit for SQL Starters

    - by Davide Mauri
    I’ve received a buch of emails from PASS Summit “First Timers” that are also somehow new to SQL Server (for “somehow” I mean people with less than 6 month experience but with some basic knowledge of SQL Server engine) or are catching up from SQL Server 2000. The common question regards the session one should not miss to have a broad view of the entire SQL Server platform have some insight into some specific areas of SQL Server Given that I’m on (semi-)vacantion and that I have more free time (not true, I have to prepare slides & demos for several conferences, PASS Summit  - Building the Agile Data Warehouse with SQL Server 2012 - and PASS 24H - Agile Data Warehousing with SQL Server 2012 - among them…but let’s pretend it to be true), I’ve decided to make a post to answer to this common questions. Of course this is my personal point of view and given the fact that the number and quality of session that will be delivered at PASS Summit is so high that is very difficoult to make a choice, fell free to jump into the discussion and leave your feedback or – even better – answer with another post. I’m sure it will be very helpful to all the SQL Server beginners out there. I’ve imposed to myself to choose 6 session at maximum for each Track. Why 6? Because it’s the maximum number of session you can follow in one day, and given that all the session will be on the Summit DVD, they are the answer to the following question: “If I have one day to spend in training, which session I should watch?”. Of course a Summit is not like a Course so a lot of very basics concept of well-established technologies won’t be found here. Analysis Services, Integration Services, MDX are not part of the Summit this time (at least for the basic part of them). Enough with that, let’s start with the session list ideal to have a good Overview of all the SQL Server Platform: Geospatial Data Types in SQL Server 2012 Inside Unstructured Data: SQL Server 2012 FileTable and Semantic Search XQuery and XML in SQL Server: Common Problems and Best Practice Solutions Microsoft's Big Play for Big Data Dashboards: When to Choose Which MSBI Tool Microsoft BI End-User Tools 360° for what concern Database Development, I recommend the following sessions Understanding Transaction Isolation Levels What to Look for in Execution Plans Improve Query Performance by Fixing Bad Parameter Sniffing A Window into Your Data: Using SQL Window Functions Practical Uses and Optimization of New T-SQL Features in SQL Server 2012 Taking MERGE Beyond the Basics For Business Intelligence Information Delivery Analyzing SSAS Data with Excel Building Compelling Power View Reports Managed Self-Service BI PowerPivot 101  SharePoint for Business Intelligence The Best Microsoft BI Tools You've Never Heard Of and for Business Intelligence Architecture & Development BI Power Hour Building a Tabular Model Database Enterprise Information Management: Bringing Together SSIS, DQS, and MDS SSIS Design Patterns Storing Columnstore Indexes Hadoop and Its Ecosystem Components in Action Beside the listed sessions, First Timers should also take a look the the page PASS set up for them: http://www.sqlpass.org/summit/2012/Connect/FirstTimers.aspx See you at PASS Summit!

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  • I didn't mean to become a database developer, but now I am. Should I stop or try to get better?

    - by pretlow majette
    20 years ago I couldn't afford even a cheap POS program when I opened my first surf shop in the Virgin Islands. I bought a copy of Paradox (remember that?) in 1990 and spent months in a back room scratching out a POS application. Over many iterations, including a switch to Access (2000)/SQL Server (2003), I built a POS and backoffice solution that runs four stores with multiple cash registers, a warehouse and office. Until recently, all my stores were connected to the same LAN (in a small shopping center) and performance wasn't an issue. Now that we've opened a location in the States that's changed. Connecting to my local server via the internet has slowed that locations application to a crawl. This is partly due to the slow and crappy dsl service we have in the Virgin Islands, and partly due to my less-than-professional code and sql. With other far-away stores in the works, I need a better solution. I like my application. My staff knows it well, and I'm not inclined to take on the expense of a proper commercial solution. So where does that leave me? I should probably host my sql online to sidestep the slow dsl here. I think I can handle cleaning up my SQL querries to speed that up a bit. What about Access? My version seems so old, but I don't like the newer versions with the 'ribbon'. There are so many options... Should I be learning Visual Studio with an eye on moving completely to the web? Will my VBA skills help me at all there? I don't have the luxury of a year at the keyboard to figure it out anymore. What about dotnetnuke, sharepoint, or lightswitch? They all seem like possibilities, but even understanding their capabilities is daunting. I'm pretty deep into it, but maybe I should bail and hire a consultant or programmer. That sounds expensive tho, and there's no guarantee there either... Any advice would be greatly appreciated. Or, if anybody is interested in buying a small chain of surf shops...

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  • Configuring trace file size and number in WebCenter Content 11g

    - by Kyle Hatlestad
    Lately I've been doing a lot of debugging using the System Output tracing in WebCenter Content 11g.  This is built-in tracing in the content server which provides a great level of detail on what's happening under the hood.  You can access the settings as well as a view of the tracing by going to Administration -> System Audit Information.  From here, you can select the tracing sections to include.  Some of my personal favorites are searchquery,  systemdatabase, userstorage, and indexer.  Usually I'm trying to find out some information regarding a search, database query, or user information.  Besides debugging, it's also very helpful for performance tuning. One of the nice tricks with the tracing is it honors the wildcard (*) character.  So you can put in 'schema*' and gather all of the schema related tracing.  And you can notice if you select 'all' and update, it changes to just a *.   To view the tracing in real-time, you simply go to the 'View Server Output' page and the latest tracing information will be at the bottom. This works well if you're looking at something pretty discrete and the system isn't getting much activity.  But if you've got a lot of tracing going on, it would be better to go after the trace log file itself.  By default, the log files can be found in the <content server instance directory>/data/trace directory. You'll see it named 'idccs_<managed server name>_current.log.  You may also find previous trace logs that have rolled over.  In this case they will identified by a date/time stamp in the name.  By default, the server will rotate the logs after they reach 1MB in size.  And it will keep the most recent 10 logs before they roll off and get deleted.  If your server is in a cluster, then the trace file should be configured to be local to the node per the recommended configuration settings. If you're doing some extensive tracing and need to capture all of the information, there are a couple of configuration flags you can set to control the logs. #Change log size to 10MB and number of logs to 20FileSizeLimit=10485760FileCountLimit=20 This is set by going to Admin Server -> General Configuration and entering them in the Additional Configuration Variables: section.  Restart the server and it should take on the new logging settings. 

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  • What will be the better way for data retrieval on application that needs to handle limited amount of data.?

    - by Milanix
    This is not really a coding question since, I am not adding any code in here. Since, adding my code snippets itself would make this question really long. Instead, I am pretty interested in knowing a better ways for data retrieval on application that needs to handle limited amount of data which isn't updated regularly. Let's take this example: I am writing an application which gets a schedule as an XML from server. I have written a logic in order to parse XML version and update database only if the version is newer than the local version. Although the update is checked automatically/manually on daily basis based on user preference, the actual version update happens only once per few months or so. Since, this is done by some other authority which doesn't provide API but, rather inform publicly on their changes. The actual XML contains a "(n number of groups)(days in a week) (n number of schedule)" . The group is usually 6 and the number of schedule is usually 2. So basically there would usually be only around 100 strings. Now although I have used SQLite at the moment. I want to know how to make update on database. Should I show progress dialog that the application is updating and exit the app when it's done? Since, my updates are infrequent i don't think this will really harm user experience but, is there any better ways to do it? Because I don't want update to be made when user is searching which is done using database. This will cause an database already open exception. Atleast I have faced this problem before. Is it better to rather parse XML every time when user wants to view certain things or to use SQLite? Since, I make lots of use of adapter in my app to create lists, will that degrade the performance? It would really be a great help if anyone can give me better overview about it. Or may be counter argument against each. Many thanks!

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  • New Features Of WordPress 3.3 You Must Know

    - by Gopinath
    After months of beta testing, WordPress 3.3 version is going to be released at the end of this month. There are several new features packed in the new version and few of them are going to excite WordPress admins. In this post we are going to discuss about the exciting new features. 1. Drag and Drop Media Uploads One of the biggest improvements in this version of WordPress is it’s all new media uploader. Now you can upload multiple files by just dragging & dropping, instantly resize  the images and filter files by their type. The media upload sports a brand new look WordPress adopted the Pupload plugin to power its media uploader component and it’s written by the same team who created the popular TinyMCE editor plugin. 2. Improved Admin Bar(Toolbar) The admin bar or newly called toolbar has got handful of makeovers. The not so much used items like Search box and other elements are removed to make sure that the bar is not clumsy. The user menu and the related options are moved to the right like how we see in Google’s user bar. Also there are few changes to the colour of the bar to make it more eye friendly. 3. Fly out Admin Menus All the left side bar menus of WordPress admin are now sports a fly out menu style to save a click. In the previous versions if you want to access a sub menu on the left side bar, you need to first click on the category and then choose the menu item from the expanded list. Now on just mouse over you will see a flyout of menu items. 4. Adaptive Admin – Layout Auto Adjust To Fit Various Devices If you own an iPad or any other so called tablets then you are going to love this feature. The admin site of WordPress has got a lot more friendly with tablets and smartphones. WordPress now auto adjusts layout to fit the device through which you are accessing the admin site.  Accessing admin dashboard on your tablets is going to be more fun. 5. Other Features Now that we have read the most useful 4 features here is a small list of other features that may interest you Nice Tooltips are displayed where ever possible to help the newbies to understand the usage of admin site Responsive Layouts jQuery 1.7 and jQuery UI 1.8.16 are the power horses of WordPress Performance improvements This article titled,New Features Of WordPress 3.3 You Must Know, was originally published at Tech Dreams. Grab our rss feed or fan us on Facebook to get updates from us.

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  • How to perform Cross Join with Linq

    - by berthin
    Cross join consists to perform a Cartesian product of two sets or sequences. The following example shows a simple Cartesian product of the sets A and B: A (a1, a2) B (b1, b2) => C (a1 b1,            a1 b2,            a2 b1,            a2, b2 ) is the Cartesian product's result. Linq to Sql allows using Cross join operations. Cross join is not equijoin, means that no predicate expression of equality in the Join clause of the query. To define a cross join query, you can use multiple from clauses. Note that there's no explicit operator for the cross join. In the following example, the query must join a sequence of Product with a sequence of Pricing Rules: 1: //Fill the data source 2: var products = new List<Product> 3: { 4: new Product{ProductID="P01",ProductName="Amaryl"}, 5: new Product {ProductID="P02", ProductName="acetaminophen"} 6: }; 7:  8: var pricingRules = new List<PricingRule> 9: { 10: new PricingRule {RuleID="R_1", RuleType="Free goods"}, 11: new PricingRule {RuleID="R_2", RuleType="Discount"}, 12: new PricingRule {RuleID="R_3", RuleType="Discount"} 13: }; 14: 15: //cross join query 16: var crossJoin = from p in products 17: from r in pricingRules 18: select new { ProductID = p.ProductID, RuleID = r.RuleID };   Below the definition of the two entities using in the above example.   1: public class Product 2: { 3: public string ProductID { get; set; } 4: public string ProductName { get; set; } 5: } 1: public class PricingRule 2: { 3: public string RuleID { get; set; } 4: public string RuleType { get; set; } 5: }   Doing this: 1: foreach (var result in crossJoin) 2: { 3: Console.WriteLine("({0} , {1})", result.ProductID, result.RuleID); 4: }   The output should be similar on this:   ( P01   -    R_1 )   ( P01   -    R_2 )   ( P01   -    R_3 )   ( P02   -    R_1 )   ( P02   -    R_2 )   ( P02   -    R_3) Conclusion Cross join operation is useful when performing a Cartesian product of two sequences object. However, it can produce very large result sets that may caused a problem of performance. So use with precautions :)

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  • How can I optimize Apache to use 1GB of RAM on my website? [closed]

    - by Markon
    My VPS plan gives me 1GB of RAM burstable to 2GB. Of course I cannot use 2 GB, nor 1 GB, everyday, so I'm planning to optimize the performance of my webserver. The average of hits-per-hour is about 8'000-10'000. This means about 2 connections-per-second. Max hits-per-hour reached until now is about 60'000. That means about 16 connections-per-second. Unluckily my current apache configuration uses too much memory (when there are not connected clients - usually during the night - it uses about 1GB) so I've tried to customize the apache installation to fit to my needs. I'm using Ubuntu, kernel 2.6.18, with apache2-mpm-worker, since I've read it requires less memory, and fcgid ( + PHP). This is my /etc/apache2/apache2.conf: Timeout 45 KeepAlive on MaxKeepAliveRequests 100 KeepAliveTimeout 10 <IfModule mpm_worker_module> StartServer 2 MinSpareThreads 25 MaxSpareThreads 75 MaxClients 100 MaxRequestsPerChild 0 </IfModule> This is the output of ps aux: www-data 9547 0.0 0.3 423828 7268 ? Sl 20:09 0:00 /usr/sbin/apache2 -k start root 17714 0.0 0.1 76496 3712 ? Ss Feb05 0:00 /usr/sbin/apache2 -k start www-data 17716 0.0 0.0 75560 2048 ? S Feb05 0:00 /usr/sbin/apache2 -k start www-data 17746 0.0 0.1 76228 2384 ? S Feb05 0:00 /usr/sbin/apache2 -k start www-data 20126 0.0 0.3 424852 7588 ? Sl 19:24 0:02 /usr/sbin/apache2 -k start www-data 24260 0.0 0.3 424852 7580 ? Sl 19:42 0:01 /usr/sbin/apache2 -k start while this is ps aux for php5: www-data 7461 2.9 2.2 142172 47048 ? S 19:39 1:39 /usr/lib/cgi-bin/php5 www-data 23845 1.3 1.7 135744 35948 ? S 20:17 0:15 /usr/lib/cgi-bin/php5 www-data 23900 2.0 1.7 136692 36760 ? S 20:17 0:22 /usr/lib/cgi-bin/php5 www-data 27907 2.0 2.0 142272 43432 ? S 20:00 0:43 /usr/lib/cgi-bin/php5 www-data 27909 2.5 1.9 138092 40036 ? S 20:00 0:53 /usr/lib/cgi-bin/php5 www-data 27993 2.4 2.2 142336 47192 ? S 20:01 0:50 /usr/lib/cgi-bin/php5 www-data 27999 1.8 1.4 135932 31100 ? S 20:01 0:38 /usr/lib/cgi-bin/php5 www-data 28230 2.6 1.9 143436 39956 ? S 20:01 0:54 /usr/lib/cgi-bin/php5 www-data 30708 3.1 2.2 142508 46528 ? S 19:44 1:38 /usr/lib/cgi-bin/php5 As you can see it use a lot of memory. How can I reduce it to fit to just 1GB of RAM? PS: I also think about the switch to nginx, if Apache can't fit to my needs...

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  • Is there a usage count for packages or programs?

    - by math
    Motivation: I want to remove applications I do not use to speed up my package processing tasks like dist upgrades, regular updates, but also for saving disk space and other reasons. I know this is a complex topic so first I will ask my question and second I will give some answers I already found out. Question: How do I find out which package I did not used at all? For example I always use the VLC so I could remove totem package. (Which I could have been used some day, yes.) Of course package dependencies could force me to have programs installed which I will never use. Notes: Find the packages which consume much space via synaptic: Select "Status" in lower left, select "Installed" in upper left, sort column on "size" in upper right. Then you can decide which big packages you really need. Use aptitude autoremove Use ubuntu-tweak's Janitor for removing old kernel packages, old configs, apt-cache entries, etc. Manually search for applications for a given task that you usually solve with your standard app. E.g. Movie player, Music player, Office program, Browser etc. (BTW: this is what I want to be helped with my question) When removing packages I always favour "apt-get purge" over "aptitude remove --purge" as aptitude often will also remove essential packages due to package dependencies. E.g. when removing "evolution" (as I use thunderbird) aptitude wants to remove also "ubuntu-desktop" and 756 other packages as well, while apt-get just removes evolution and its helping pacakges like evolution-common. Ubuntu lense gives me most recent used applications which are candidates for keeping :) Employ deborphan as I read in this related answer: How do I clean up my harddrive? I should certainly keep essential packages: Keep only essential packages This question is pretty much a duplicate of How to see what installed packages I have never used for cleaning purposes but covering only few aspects. However one answer suggests to use a program called unusedpkg but the link seems down. There is also a program called Kleen http://code.google.com/p/kleen/ but it won't compile in 11.10. However I hacked it to compile but the results are unusable, as for example the g++ package was marked as not used for 203, but actually I used it seconds ago for compiling Kleen itself ;) So don't use this tool. On http://wiki.debian.org/DebianPackageInformation I read the the package popularity-contest will produce log files with usage statistics. Unfortunately I didn't enabled the popularity contest so I can't find this log file.

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  • SQL Saturday 194 - Exeter

    - by Dave Ballantyne
    Many kudos goes to Jonathan and Annette Allen and the others on the team for confirming SQL Saturday 194 in Exeter on the 8th and 9th of March.  The event home page is here http://www.sqlsaturday.com/194/eventhome.aspx and I delighted that myself and Dave Morrison will be presenting a full day pre-con on the 8th on favourite subjects “TSQL and Internals”. Here is the full abstract : TSQL and internals - When faced with performance issues there are many lines of attack. Tuning the engine itself can get you so far, however for maximum effect you need to understand how the engine and how it translates SQL statements into performable actions. This is not a simple task, it is a massive task to deal with a multi-table join and the number of permutations can be immense. To back up this knowledge, we can create better performing TSQL and understand the impact that is has upon the engine and recognize the pitfalls and gotcha’s that exist in SQLServer. Ultimately, there is no ‘best way’ to perform a single task only many variations of ‘it depends’ , but now we can pick the most appropriate option for the required dataload. Over the years, there have been many myths and misconceptions have grown around the product, some have basis in older versions and some are just wrong. Continuing to build on the knowledge given so far these issue will be explored and broken down and proved or disproved. Finally we will look to the future and explore SQL Server 2012 and the new functionality that that brings and some of the common uses that we will be able to address. After completion of this days pre-con, attendees will have a more complete knowledge of execution plans, and how they relate to the physical and logical actions that SQLServer will be executing on their behalf. The attendees will also have a more rounded and fuller knowledge of TSQL and the implications of incorrectly defining a query. Dave is a fountain of knowledge on execution plans and optimizer internals and ,though i may flatter myself, I’m no shrinking violet when it comes to TSQL and such matters.  I hope that if you cant join us, then there are other pre-cons available from other experts in their fields that may ‘float you boat’ too.  The pre-con page is http://sqlsouthwest.co.uk/SQLSaturday_precon.htm Also, excitingly, this pre-con day is sponsored by Fusion-IO which is a great boon for the day. If you want a more of this then i am offering a 2 day TSQL course starting on the 19th of March. More details on this are available here

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  • Is IE9 a modern browser?

    - by anirudha
    Is IE9 a modern browser? i show you a post who compare IE as well as they compare chrome. Is IE9 a modern browser? well Are you thing that they make something bettter then thing another that what Firefox and chrome do whenever Microsoft do this. that's point that Microsoft always blast IE because they make version upon version not upon update like Firefox make 3.6.14 after 3.6.13 and chrome give update soon as possible but IE not come soon. they will thing for making 10 instead of giving update on 9. well what they tell us new. they make fool public everytime i believe they make fool public as same as today they maked for version 9 they show developer tool in 9 have three new tabs or pael are this enough. whenever  in chrome and firefox their is many plugin who make development easier IE still have a developer tool who not have enough power like Firebug in Firefox. they show performance but forget luna user [window xp] and their IE never runs on other plateform but chrome and firefox can. no customization in IE whenever chrome and firefox have uncountable plugin and addons. show features now in IE who already implemented in firefox very early. well their is no rule that static goes right every time not sure that IE and Firefox both are right in their language. their is no one predict what thing goes better in future. so well keep a thing in mind never wasted time and also thing to make task easier even you need to use sollution opensource or closesoure inside or outside MS does not matter. well everyone tell you much more then they do even IE and some other. they never tell you this thing not in IE but in another can be found they never tell you use other whenever you need a thing and never can be found in their software. you need to more beware of IE because they make them commorcial not really for public if really then why they stop wxp user to use them as well firefox and chrome never force. because they need a thing that force more then more copy of windows sale. so they thing to add a thing in window 8. the IE9 they thing to make before that they thing to make  this for windows 8. they always force user to purchase this for this. this for this. and this trick sell their software. well outside MS Mozilla and Chrome all behave better with user and their feedback. they respect user their privacy and feedback. if you not believe that how much problem you found in IE and they got solved soon as in chrome and firefox bug kill soon. because IE not opensource we need to  boycutt them secondly their is no customization then they make user task easier even with twitter and facebook.

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  • An Unstoppable Force!

    - by TammyBednar
    Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin-top:0in; mso-para-margin-right:0in; mso-para-margin-bottom:10.0pt; mso-para-margin-left:0in; line-height:115%; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} Building a high-availability database platform presents unique challenges. Combining servers, storage, networking, OS, firmware, and database is complicated and raises important concerns: Will coordination between multiple SME’s delay deployment? Will it be reliable? Will it scale? Will routine maintenance consume precious IT-staff time? Ultimately, will it work? Enter the Oracle Database Appliance, a complete package of software, server, storage, and networking that’s engineered for simplicity. It saves time and money by simplifying deployment, maintenance, and support of database workloads. Plus, it’s based on Intel Xeon processors to ensure a high level of performance and scalability. Take a look at this video to compare Heather and Ted’s approach to building a server for their Oracle database! http://www.youtube.com/watch?v=os4RDVclWS8 If you missed the “Compare Database Platforms: Build vs. Buy” webcast or want to listen again to find out how Jeff Schulte - Vice President at Yodlee uses Oracle Database Appliance.

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  • Oracle OpenWorld is on the Horizon

    - by Matthew Haavisto
    Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} Oracle OpenWorld 2012 is only a few months away, and we're excited about our slate of sessions and other activities scheduled this year.  PeopleSoft sessions are perennially among the best attended and well-received sessions, and we plan to keep that trend going. We have a full complement of sessions planned, from updates for some of your yearly favorites to lots of completely new topics.  Some of the long-standing favorites include the PeopleSoft Technology Roadmap, PeopleTools Tips and Techniques and a number of candid panel discussions. Coverage of the latest trends include new sessions on PeopleSoft on mobile platforms, PeopleSoft's new user experience and interaction model, advances in reporting and analytics and employing virtualization to reduce costs.  The PeopleTools team is also working closely with Applications groups this year to demonstrate to users how advances in PeopleTools will have a direct and beneficial impact on the latest applications releases.  There are plenty of sessions for developers and administrators as well, from sessions on enhancing, integrating, maintaining, and securing your applications, to tuning for performance.  We'll also update you on the latest platform roadmap. In addition to these conventional sessions, we will of course be manning the demo pods, where you'll be able to see the latest functionality first hand. We plan to engage in lots of direct customer interaction.  One of the highlights each year for our team as well as attendees is the session in which a panel of senior PeopleTools leaders talks candidly and engages in open Q&A with customers about our products.  This is definitely a discussion worth joining in on. Keep your eyes on this blog in the coming weeks for details on many of the sessions we have planned.  We look forward to seeing you at OpenWorld 2012!

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  • Movement prediction for non-shooters

    - by ShadowChaser
    I'm working on an isometric (2D) game with moderate-scale multiplayer - 20-30 players. I've had some difficulty getting a good movement prediction implementation in place. Right now, clients are authoritative for their own position. The server performs validation and broad-scale cheat detection, and I fully realize that the system will never be fully robust against cheating. However, the performance and implementation tradeoffs work well for me right now. Given that I'm dealing with sprite graphics, the game has 8 defined directions rather than free movement. Whenever the player changes their direction or speed (walk, run, stop), a "true" 3D velocity is set on the entity and a packet it sent to the server with the new movement state. In addition, every 250ms additional packets are transmitted with the player's current position for state updates on the server as well as for client prediction. After the server validates the packet, it gets automatically distributed to all of the other "nearby" players. Client-side, all entities with non-zero velocity (ie/ moving entities) are tracked and updated by a rudimentary "physics" system - basically nothing more than changing the position by the velocity according to the elapsed time slice (40ms or so). What I'm struggling with is how to implement clean movement prediction. I have the nagging suspicion that I've made a design mistake somewhere. I've been over the Unreal, Half-life, and all other movement prediction/lag compensation articles I could find, but they all seam geared toward shooters: "Don't send each control change, send updates every 120ms, server is authoritative, client predicts, etc". Unfortunately, that style of design won't work well for me - there's no 3D environment so each individual state change is important. 1) Most of the samples I saw tightly couple movement prediction right into the entities themselves. For example, storing the previous state along with the current state. I'd like to avoid that and keep entities with their "current state" only. Is there a better way to handle this? 2) What should happen when the player stops? I can't interpolate to the correct position, since they might need to walk backwards or another strange direction if their position is too far ahead. 3) What should happen when entities collide? If the current player collides with something, the answer is simple - just stop the player from moving. But what happens if two entities take up the same space on the server? What if the local prediction causes a remote entity to collide with the player or another entity - do I stop them as well? If the prediction had the misfortune of sticking them in front of a wall that the player has gone around, the prediction will never be able to compensate and once the error gets to high the entity will snap to the new position.

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  • Draw images with warped triangles on a web server [migrated]

    - by epologee
    The scenario The Flash front end of my current project produces images that a web server needs to combine into a video. Both frame-rate and frame-resolution are sizeable enough that sending an image sequence to the back end is not feasible (in both time and client bandwidth). Instead, we're trying to recreate the image drawing on the back end as well. Correct and slow, or incorrect and fast The problem is that this involves quite a bit of drawing textured triangles, and two solutions we found in Python (here and there) are so inefficient, that the drawing takes about 60 seconds per frame, resulting in a whopping 7,5 hours of processing time for a 30 second clip. Unacceptable. When using a PHP-module to send commands to ImageMagick for image manipulation, the whole process is super fast (tenths of a second per frame), but ImageMagick seems to be unable to draw triangles the way we do it in the front end, so the final results do not match. Unacceptable. What I'm asking here, is if there's someone who would know a way to solve this issue, by any means necessary that would run on a web server. Warping an image Let me explain the process of the front end: Perform a Delaunay calculation on points in an image to get an evenly distributed mesh of triangles. Offset the points/vertices in the mesh, distorting or warping the image. Draw the warped triangles on a new bitmap. We can send the results (coordinates) of steps 1 and 2 to the back end, to then draw the warped triangles and save it to an image on disk (or append as a frame to the video). But that last step is what I need help with. The Question Is there an alternative to ImageMagick that can draw triangles in a bitmap? Is there some other library, like a C library, that would allow us to do this? Or could we achieve this effect more easily by switching back end technologies, like Ruby? (.Net and Java are, unfortunately, not really options right now) Many thanks. EP. P.S. I'd appreciate re-tagging efforts, I don't quite know what labels to put on this question. Thanks!

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  • Collaborative work (small team) - Best practices

    - by LEM01
    I'm currently working in a very small team of programmers (2-3) and I'm looking for advices/best practices on how to organise our work. We're all working on the same application using PHP. Today we're kind of all working on our way. Today situation: List item that have to be worked on by each dev 1/week. What has to be done is defined at a high functional level (ex: Build the search engine for this product..) Commit / merge our individual branches (git) every week before the next meeting No real dev rules, no code review No test written (aouutch) Problems faced: Code quality issue: discovering someone else code is sometime tough (inline, variable+function+class names, spaces, comments..) Changes in already existing classes (impact on someone else work) Responsibility of each dev unclear: after getting someone else code and discover something messy, should I make the change? Should he make the change? How to plan those things,... What I'm looking for: Basically I'm looking into structuring the way we develop things in order to avoid frustration and improve overall quality. How to define coding standards (naming convention, code rules...)? Do you you any validation script to make sure code is valid before committing? Do you think that defining an architect role in the team is needed? Someone that would actually define what has to be developed during the next phase. By defining interfaces or class descriptions that have to be written. (Does it make sense in such a small team?) Today we're losing time into understanding what others did or tried to do, we're also losing time in discussion like "you should have done it that way! Why is this class doing that and not that..? Shouldn't we have a embedded class rather that this set of data...". I'm looking into a work process, maybe with more defined responsibilities and process in order to improve our performance. If you have experience, advices, best practices or anything to share that we could benefit from it will be much appreciated! Thanks a lot for your time!

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  • Why is everything crashing?

    - by Kopkins
    I've been using Ubuntu for a while now and I love it, I wouldn't think of using another OS unless I can't fix this issue. The install I'm on is only around a month and a half old. I'm running 12.04 64bit on a 8,1 MBP. Up until around 2 weeks ago everything was running smoothly. Around then applications started crashing and weird things started happening. At first I thought it was just certain applications. The first thing to start giving me trouble was compiz. Occasionally compiz will stop decorating windows and lost many other functionalities. running compiz --replace fixes this, but I don't feel like doing it usually once a day. The other thing with this is that after running compiz --replace, my conky window gets lost somewhere and so I run killall conky && conky -c .conkyrc. But this isn't with just a couple applications, it seems like it is proliferating through my system. Last week fontforge started crashing while doing whatever task. So I ended up unable to finish what I was working on to completeness. Didn't find a fix. Today rhythmbox started crashing. Whenever I try to play anything, Rhythmbox becomes unresponsive and needs to be forced to close. When I try to do certain things with the disk utility, it crashes. I get the Ubuntu has experienced an internal error message much more often than I would like. Frequently applications stop appearing in the launcher. Wine almost never does anymore. After not being active for a little while, thunderbird can only fetch my mail after restarting wireless, sudo rmmod b43 && sudo modprobe b43 Occasionally some of my startup apps don't start. What is my best option here? Could they be bugs? I don't want to submit a ton of vague bug reports. Reinstall? switch OS? Thank you to anyone who responds. Kopkins

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  • Best way to determine surface normal for a group of pixels?

    - by Paul Renton
    One of my current endeavors is creating a 2D destructible terrain engine for iOS Cocos2D (See https://github.com/crebstar/PWNDestructibleTerrain ). It is in an infant stages no doubt, but I have made significant progress since starting a couple weeks ago. However, I have run into a bit of a performance road block with calculating surface normals. Note: For my destructible terrain engine, an alpha of 0 is considered to not be solid ground. The method posted below works just great given small rectangles, such as n < 30. Anything above 30 causes a dip in the frame rate. If you approach 100x100 then you might as well read a book while the sprite attempts to traverse the terrain. At the moment this is the best I can come up with for altering the angle on a sprite as it roams across terrain (to get the angle for a sprite's orientation just take dot product of 100 * normal * (1,0) vector). -(CGPoint)getAverageSurfaceNormalAt:(CGPoint)pt withRect:(CGRect)area { float avgX = 0; float avgY = 0; ccColor4B color = ccc4(0, 0, 0, 0); CGPoint normal; float len; for (int w = area.size.width; w >= -area.size.width; w--) { for (int h = area.size.height; h >= -area.size.height; h--) { CGPoint pixPt = ccp(w + pt.x, h + pt.y); if ([self pixelAt:pixPt colorCache:&color]) { if (color.a != 0) { avgX -= w; avgY -= h; } // end inner if } // end outer if } // end inner for } // end outer for len = sqrtf(avgX * avgX + avgY * avgY); if (len == 0) { normal = ccp(avgX, avgY); } else { normal = ccp(avgX/len, avgY/len); } // end if return normal; } // end get My problem is I have sprites that require larger rectangles in order for their movement to look realistic. I considered doing a cache of all surface normals, but this lead to issues of knowing when to recalculate the surface normals and these calculations also being quite expensive (also how large should the blocks be?). Another smaller issue is I don't know how to properly treat the case when length is = 0. So I am stuck... Any advice from the community would be greatly appreciated! Is my method the best possible one? Or should I rethink the algorithm? I am new to game development and always looking to learn new tips and tricks.

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  • Weird Ubuntu Desktop Boot Partition On External Hard Drive

    - by Magnitus
    I have a Thinkpad with Windows 7. Last time I installed an Ubuntu/Windows dual boot, Windows was never same after and regularly got corrupted so this time, I installed Ubuntu on a separate external hard drive. I took a 500 GB external hard drive and used Windows to shrink the partition on it to 400 GB, freeing 100 GB to install Ubuntu. Then I modified the booting priority of my computer to boot from the external hard drive if present. Then, I installed Ubuntu desktop on the external hard drive using a DVD, picked the most simplistic partitioning scheme I could get away with (didn't go auto as it didn't include the external hard drive as a choice) and voilà. Fast forward some time and I'm trying to refresh my understanding of Linux partitions to install a bunch of servers, so I'm looking at the current partitioning scheme on my external hard drive and find the boot partition puzzling... sda is my integrated hard drive with Windows 7. sdb is my Ubuntu desktop external hard drive. Running parted on sdb, I get this: (parted) print Model: WD My Passport 0740 (scsi) Disk /dev/sdb: 500GB Sector size (logical/physical): 512B/512B Partition Table: msdos Number Start End Size Type File system Flags 1 1049kB 393GB 393GB primary ntfs boot 2 393GB 500GB 107GB extended 5 393GB 425GB 32.8GB logical linux-swap(v1) 6 425GB 500GB 74.6GB logical ext4 At this point, I'm wondering why the ntfs partition is flagged as "boot" and not my ext4 partition which is the partition that contains / (and by extension, /boot since it's not on its own separate partition). Looking at mtab only confirms what I already know: eric@eric-ThinkPad-W530:~$ sudo cat /etc/mtab /dev/sdb6 / ext4 rw,errors=remount-ro 0 0 proc /proc proc rw,noexec,nosuid,nodev 0 0 sysfs /sys sysfs rw,noexec,nosuid,nodev 0 0 none /sys/fs/cgroup tmpfs rw 0 0 none /sys/fs/fuse/connections fusectl rw 0 0 none /sys/kernel/debug debugfs rw 0 0 none /sys/kernel/security securityfs rw 0 0 udev /dev devtmpfs rw,mode=0755 0 0 devpts /dev/pts devpts rw,noexec,nosuid,gid=5,mode=0620 0 0 tmpfs /run tmpfs rw,noexec,nosuid,size=10%,mode=0755 0 0 none /run/lock tmpfs rw,noexec,nosuid,nodev,size=5242880 0 0 none /run/shm tmpfs rw,nosuid,nodev 0 0 none /run/user tmpfs rw,noexec,nosuid,nodev,size=104857600,mode=0755 0 0 none /sys/fs/pstore pstore rw 0 0 systemd /sys/fs/cgroup/systemd cgroup rw,noexec,nosuid,nodev,none,name=systemd 0 0 gvfsd-fuse /run/user/1000/gvfs fuse.gvfsd-fuse rw,nosuid,nodev,user=eric 0 0 /dev/sdb1 /media/eric/My\040Passport fuseblk rw,nosuid,nodev,allow_other,default_permissions,blksize=4096 0 0 My lack of understanding concerning this is not vital to anything (this is only my development desktop partition), but somehow annoys me. Any insight that could shed some light on this would be welcome.

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  • PHP - Internal APIs/Libraries - What makes sense?

    - by Mark Locker
    I've been having a discussion lately with some colleagues about the best way to approach a new project, and thought it'd be interesting to get some external thoughts thrown into the mix. Basically, we're redeveloping a fairly large site (written in PHP) and have differing opinions on how the platform should be setup. Requirements: The platform will need to support multiple internal websites, as well as external (non-PHP) projects which at the moment consist of a mobile app and a toolbar. We have no plans/need in the foreseeable future to open up an API externally (for use in products other than our own). My opinion: We should have a library of well documented native model classes which can be shared between projects. These models will represent everything in our database and can take advantage of object orientated features such as inheritance, traits, magic methods, etc. etc. As well as employing ORM. We can then add an API layer on top of these models which can basically accept requests and route them to the appropriate methods, translating the response so that it can be used platform independently. This routing for each method can be setup as and when it's required. Their opinion: We should have a single HTTP API which is used by all projects (internal PHP ones or otherwise). My thoughts: To me, there are a number of issues with using the sole HTTP API approach: It will be very expensive performance wise. One page request will result in several additional http requests (which although local, are still ones that Apache will need to handle). You'll lose all of the best features PHP has for OO development. From simple inheritance, to employing the likes of ORM which can save you writing a lot of code. For internal projects, the actual process makes me cringe. To get a users name, for example, a request would go out of our box, over the LAN, back in, then run through a script which calls a method, JSON encodes the output and feeds that back. That would then need to be JSON decoded, and be presented as an array ready to use. Working with arrays, as appose to objects, makes me sad in a modern PHP framework. Their thoughts (and my responses): Having one method of doing thing keeps things simple. - You'd only do things differently if you were using a different language anyway. It will become robust. - Seeing as the API will run off the library of models, I think my option would be just as robust. What do you think? I'd be really interested to hear the thoughts of others on this, especially as opinions on both sides are not founded on any past experience.

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  • Unintentional run-in with C# thread concurrency

    - by geekrutherford
    For the first time today we began conducting load testing on a ASP.NET application already in production. Obviously you would normally want to load test prior to releasing to a production environment, but that isn't the point here.   We ran a test which simulated 5 users hitting the application doing the same actions simultaneously. The first few pages visited seemed fine and then things just hung for a while before the test failed. While the test was running I was viewing the performance counters on the server noting that the CPU was consistently pegged at 100% until the testing tool gave up.   Fortunately the application logs all exceptions including those unhandled to the database (thanks to log4net). I checked the log and low and behold the error was:   System.ArgumentException: An item with the same key has already been added. (The rest of the stack trace intentionally omitted)   Since the code was running with debug on the line number where the exception occured was also provided. I began inspecting the code and almost immediately it hit me, the section of code responsible for the exception is trying to initialize a static class. My next question was how is this code being hit multiple times when I have a rudimentary check already in place to prevent this kind of thing (i.e. a check on a public variable of the static class before entering the initializing routine). The answer...the check fails because the value is not set before other threads have already made it through.   Not being one who consistently works with threading I wasn't quite sure how to handle this problem. Fortunately a co-worker recalled having to lock a section of code in the past but couldn't recall exactly how. After a quick search on Google the solution is as follows:   Object objLock = new Object(); lock(objLock) { //logic requiring lock }   The lock statement takes an object and tells the .NET runtime that the current thread has exclusive access while the code within brackets is executing. Once the code completes, the lock is released for another thread to utilize.   In my case, I only need to execute the inner code once to initialize my static class. So within the brackets I have a check on a public variable to prevent it from being initialized again.

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