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  • Google Chrome won't install via IE9/Windows7

    - by purir
    Using IE9, I've tried installing Google Chrome on Windows 7 from this url http://www.google.com/chrome/eula.html?hl=en-GB&platform=win But get the following error (apologies for uncouthly dumping this nonsense...) Any ideas dearly appreciated! PLATFORM VERSION INFO Windows : 6.1.7601.65536 (Win32NT) Common Language Runtime : 4.0.30319.235 System.Deployment.dll : 4.0.30319.1 (RTMRel.030319-0100) clr.dll : 4.0.30319.235 (RTMGDR.030319-2300) dfdll.dll : 4.0.30319.1 (RTMRel.030319-0100) dfshim.dll : 4.0.31106.0 (Main.031106-0000) SOURCES Deployment url : _http://dl.google.com/update2/1.3.21.57/GoogleInstaller_en-GB.application?appguid%3D%7B8A69D345-D564-463C-AFF1-A69D9E530F96%7D%26iid%3D%7B26C55C3A-B26A-0484-FEDD-78443D269DA1%7D%26lang%3Den-GB%26browser%3D2%26usagestats%3D0%26appname%3DGoogle%2520Chrome%26needsadmin%3Dfalse%26installdataindex%3Ddefaultbrowser ERROR SUMMARY Below is a summary of the errors, details of these errors are listed later in the log. * Activation of _http://dl.google.com/update2/1.3.21.57/GoogleInstaller_en-GB.application?appguid%3D%7B8A69D345-D564-463C-AFF1-A69D9E530F96%7D%26iid%3D%7B26C55C3A-B26A-0484-FEDD-78443D269DA1%7D%26lang%3Den-GB%26browser%3D2%26usagestats%3D0%26appname%3DGoogle%2520Chrome%26needsadmin%3Dfalse%26installdataindex%3Ddefaultbrowser resulted in exception. Following failure messages were detected: + The system cannot find the file specified. (Exception from HRESULT: 0x80070002) COMPONENT STORE TRANSACTION FAILURE SUMMARY No transaction error was detected. WARNINGS There were no warnings during this operation. OPERATION PROGRESS STATUS * [25/06/2011 11:41:04] : Activation of _http://dl.google.com/update2/1.3.21.57/GoogleInstaller_en-GB.application?appguid%3D%7B8A69D345-D564-463C-AFF1-A69D9E530F96%7D%26iid%3D%7B26C55C3A-B26A-0484-FEDD-78443D269DA1%7D%26lang%3Den-GB%26browser%3D2%26usagestats%3D0%26appname%3DGoogle%2520Chrome%26needsadmin%3Dfalse%26installdataindex%3Ddefaultbrowser has started. ERROR DETAILS Following errors were detected during this operation. * [25/06/2011 11:41:04] System.IO.FileNotFoundException - The system cannot find the file specified. (Exception from HRESULT: 0x80070002) - Source: System.Deployment - Stack trace: at System.Deployment.Internal.Isolation.IsolationInterop.GetUserStore(UInt32 Flags, IntPtr hToken, Guid& riid) at System.Deployment.Application.ComponentStore..ctor(ComponentStoreType storeType, SubscriptionStore subStore) at System.Deployment.Application.SubscriptionStore..ctor(String deployPath, String tempPath, ComponentStoreType storeType) at System.Deployment.Application.SubscriptionStore.get_CurrentUser() at System.Deployment.Application.ApplicationActivator.PerformDeploymentActivation(Uri activationUri, Boolean isShortcut, String textualSubId, String deploymentProviderUrlFromExtension, BrowserSettings browserSettings, String& errorPageUrl) at System.Deployment.Application.ApplicationActivator.ActivateDeploymentWorker(Object state) COMPONENT STORE TRANSACTION DETAILS No transaction information is available.

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  • How can I confirm that burn process was completed successfully??

    - by infant programmer
    Just now I tried to make a duplicate copy of my Windows XP Pro SP3 CD. I had set 32X speed while the max speed allowed is 48X. And checked "Verify the Data after burning". I didn't observe how much % did it complete. But after 15 mins (which is sufficient period to burn disc), I heard "Fatal Error" sound. When I saw the monitor, There was a message box which was showing "Error while burning Disc", I saved the error log which you can find here click_me. How do I acknowledge that burning process is done?? Well. my PC is able to read the CD and CD is bootable too.. I am not sure .. whether the burning process got failed or the verify Process! Please let me know if you have come across or aware of such situation .. As it is XP installation CD .. I don't want to do trial and error method. regards,

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  • Google Chrome won't install via IE9/Windows7

    - by purir
    Using IE9, I've tried installing Google Chrome on Windows 7 from this url http://www.google.com/chrome/eula.html?hl=en-GB&platform=win But get the following error (apologies for uncouthly dumping this nonsense...) Any ideas dearly appreciated! PLATFORM VERSION INFO Windows : 6.1.7601.65536 (Win32NT) Common Language Runtime : 4.0.30319.235 System.Deployment.dll : 4.0.30319.1 (RTMRel.030319-0100) clr.dll : 4.0.30319.235 (RTMGDR.030319-2300) dfdll.dll : 4.0.30319.1 (RTMRel.030319-0100) dfshim.dll : 4.0.31106.0 (Main.031106-0000) SOURCES Deployment url : _http://dl.google.com/update2/1.3.21.57/GoogleInstaller_en-GB.application?appguid%3D%7B8A69D345-D564-463C-AFF1-A69D9E530F96%7D%26iid%3D%7B26C55C3A-B26A-0484-FEDD-78443D269DA1%7D%26lang%3Den-GB%26browser%3D2%26usagestats%3D0%26appname%3DGoogle%2520Chrome%26needsadmin%3Dfalse%26installdataindex%3Ddefaultbrowser ERROR SUMMARY Below is a summary of the errors, details of these errors are listed later in the log. * Activation of _http://dl.google.com/update2/1.3.21.57/GoogleInstaller_en-GB.application?appguid%3D%7B8A69D345-D564-463C-AFF1-A69D9E530F96%7D%26iid%3D%7B26C55C3A-B26A-0484-FEDD-78443D269DA1%7D%26lang%3Den-GB%26browser%3D2%26usagestats%3D0%26appname%3DGoogle%2520Chrome%26needsadmin%3Dfalse%26installdataindex%3Ddefaultbrowser resulted in exception. Following failure messages were detected: + The system cannot find the file specified. (Exception from HRESULT: 0x80070002) COMPONENT STORE TRANSACTION FAILURE SUMMARY No transaction error was detected. WARNINGS There were no warnings during this operation. OPERATION PROGRESS STATUS * [25/06/2011 11:41:04] : Activation of _http://dl.google.com/update2/1.3.21.57/GoogleInstaller_en-GB.application?appguid%3D%7B8A69D345-D564-463C-AFF1-A69D9E530F96%7D%26iid%3D%7B26C55C3A-B26A-0484-FEDD-78443D269DA1%7D%26lang%3Den-GB%26browser%3D2%26usagestats%3D0%26appname%3DGoogle%2520Chrome%26needsadmin%3Dfalse%26installdataindex%3Ddefaultbrowser has started. ERROR DETAILS Following errors were detected during this operation. * [25/06/2011 11:41:04] System.IO.FileNotFoundException - The system cannot find the file specified. (Exception from HRESULT: 0x80070002) - Source: System.Deployment - Stack trace: at System.Deployment.Internal.Isolation.IsolationInterop.GetUserStore(UInt32 Flags, IntPtr hToken, Guid& riid) at System.Deployment.Application.ComponentStore..ctor(ComponentStoreType storeType, SubscriptionStore subStore) at System.Deployment.Application.SubscriptionStore..ctor(String deployPath, String tempPath, ComponentStoreType storeType) at System.Deployment.Application.SubscriptionStore.get_CurrentUser() at System.Deployment.Application.ApplicationActivator.PerformDeploymentActivation(Uri activationUri, Boolean isShortcut, String textualSubId, String deploymentProviderUrlFromExtension, BrowserSettings browserSettings, String& errorPageUrl) at System.Deployment.Application.ApplicationActivator.ActivateDeploymentWorker(Object state) COMPONENT STORE TRANSACTION DETAILS No transaction information is available.

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  • How can I confirm that burn process is completed successfully??

    - by infant programmer
    Just now I tried to make a duplicate copy of my Windows XP Pro SP3 CD. I had set 32X speed while the max speed allowed is 48X. And checked "Verify the Data after burning". I didn't observe how much % did it complete. But after 15 mins (which is sufficient period to burn disc), I heard "Fatal Error" sound. When I saw the monitor, There was a message box which was showing "Error while burning Disc", I saved the error log which you can find here click_me. How do I acknowledge that burning process is done?? Well. I my PC is able to read the cd and it is bootable too.. I am not sure .. whether the burning process got failed or the verify Process! Please let me know if you have come across or aware of such situation .. As it is XP installation CD .. I don't want to do trial and error method. regards,

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  • validate weblogic security realm user through java

    - by user1877246
    i have installed weblogic '10.3.4.0' and have created a user in the default security realm 'myrealm'. The authenticator is DefaultAuthenticator. Now, I have to authenticate the user through a stand alone java application. But the application is resposning with 'LDAP: error code 49 - Invalid Credentials': CODE-START ** Properties l_props = new Properties(); LdapContext l_ctx = null; l_props.put(Context.INITIAL_CONTEXT_FACTORY, "com.sun.jndi.ldap.LdapCtxFactory"); l_props.put(Context.PROVIDER_URL, "ldap://localhost:7001"); l_props.put(Context.SECURITY_AUTHENTICATION, "simple"); l_props.put(Context.SECURITY_PRINCIPAL, "cn=username"); l_props.put(Context.SECURITY_CREDENTIALS, "password"); l_ctx = new InitialLdapContext(l_props, null); ** CODE-END ** * ERROR-START * javax.naming.AuthenticationException: [LDAP: error code 49 - Invalid Credentials] at com.sun.jndi.ldap.LdapCtx.mapErrorCode(LdapCtx.java:3041) at com.sun.jndi.ldap.LdapCtx.processReturnCode(LdapCtx.java:2987) at com.sun.jndi.ldap.LdapCtx.processReturnCode(LdapCtx.java:2789) at com.sun.jndi.ldap.LdapCtx.connect(LdapCtx.java:2703) at com.sun.jndi.ldap.LdapCtx.(LdapCtx.java:293) at com.sun.jndi.ldap.LdapCtxFactory.getUsingURL(LdapCtxFactory.java:175) at com.sun.jndi.ldap.LdapCtxFactory.getUsingURLs(LdapCtxFactory.java:193) at com.sun.jndi.ldap.LdapCtxFactory.getLdapCtxInstance(LdapCtxFactory.java:136) at com.sun.jndi.ldap.LdapCtxFactory.getInitialContext(LdapCtxFactory.java:66) at javax.naming.spi.NamingManager.getInitialContext(NamingManager.java:667) at javax.naming.InitialContext.getDefaultInitCtx(InitialContext.java:288) at javax.naming.InitialContext.init(InitialContext.java:223) at javax.naming.ldap.InitialLdapContext.(InitialLdapContext.java:134) at com.iflex.fcat.misc.TestLDAP.createInitialLdapContext(TestLDAP.java:258) at com.iflex.fcat.misc.TestLDAP.authenticate(TestLDAP.java:170) at com.iflex.fcat.misc.TestLDAP.main(TestLDAP.java:125) ERROR-END

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  • sql server uninstallation issue

    - by angel
    I'm unable to remove SQL Server 2008 sp1 completely from my system. I'm using windows 7 ultimate. Everytime I try uninstalling it i get the following error. How can I remove it? here is the log: Overall summary: Final result: Failed: see details below Exit code (Decimal): -2068643839 Exit facility code: 1203 Exit error code: 1 Exit message: Failed: see details below Start time: 2013-06-24 21:10:38 End time: 2013-06-24 21:21:17 Requested action: Uninstall Log with failure: C:\Program Files\Microsoft SQL Server\100\Setup Bootstrap\Log\20130624_210908\sql_rs_Cpu64_1.log Exception help link: http://go.microsoft.com/fwlink?LinkId=20476&ProdName=Microsoft+SQL+Server&EvtSrc=setup.rll&EvtID=50000&ProdVer=10.0.1600.22 Machine Properties: Machine name: ABHI-PC Machine processor count: 4 OS version: Windows Vista OS service pack: Service Pack 1 OS region: United States OS language: English (United States) OS architecture: x64 Process architecture: 64 Bit OS clustered: No Product features discovered: Product Instance Instance ID Feature Language Edition Version Clustered Sql Server 2008 MSSQLSERVER MSRS10.MSSQLSERVER Reporting Services 1033 Enterprise Edition 10.0.1600.22 No Sql Server 2008 Management Tools - Basic 10.0.1600.22 No Package properties: Description: SQL Server Database Services 2008 SQLProductFamilyCode: {628F8F38-600E-493D-9946-F4178F20A8A9} ProductName: SQL2008 Type: RTM Version: 10 SPLevel: 0 Installation edition: ENTERPRISE User Input Settings: ACTION: Uninstall CONFIGURATIONFILE: C:\Program Files\Microsoft SQL Server\100\Setup Bootstrap\Log\20130624_210908\ConfigurationFile.ini FEATURES: RS,SSMS,SNAC_SDK,CE_RUNTIME,CE_TOOLS,SNAC HELP: False INDICATEPROGRESS: False INSTANCEID: INSTANCENAME: MSSQLSERVER MEDIASOURCE: QUIET: False QUIETSIMPLE: False X86: False Configuration file: C:\Program Files\Microsoft SQL Server\100\Setup Bootstrap\Log\20130624_210908\ConfigurationFile.ini Detailed results: Feature: SQL Client Connectivity Status: Skipped MSI status: Passed Configuration status: Passed Feature: SQL Client Connectivity SDK Status: Skipped MSI status: Passed Configuration status: Passed Feature: Reporting Services Status: Failed: see logs for details MSI status: Passed Configuration status: Failed: see details below Configuration error code: 0xFFD65603 Configuration error description: Input string was not in a correct format. Configuration log: C:\Program Files\Microsoft SQL Server\100\Setup Bootstrap\Log\20130624_210908\Detail.txt Feature: SQL Compact Edition Tools Status: Passed MSI status: Passed Configuration status: Passed Feature: SQL Compact Edition Runtime Status: Skipped MSI status: Passed Configuration status: Passed Feature: Management Tools - Basic Status: Failed: see logs for details MSI status: Passed Configuration status: Passed Rules with failures: Global rules: There are no scenario-specific rules. Rules report file: C:\Program Files\Microsoft SQL Server\100\Setup Bootstrap\Log\20130624_210908\SystemConfigurationCheck_Report.htm

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  • Viewing local websites on my iOS device over Wi-fi

    - by John
    Trying to view some local html/css/js files in a mobile browser on my iOS device. Thought maybe file-sharing would be an option, and is, but I'm not completely satisfied with it. Any time I try to do the following an error occurs. Web sharing is on and available at http://192.168.1.101/~user but I have to manually copy the files in. If I try to symlink a folder in so that the address could be viewed at ''~user/some_dir by issuing $ ln -s /Users/user/dev/some_dir ~/Sites/ then I get a 403 forbidden error. I've tried to remedy this by modifying a user.conf file in /private/etc/apache2/ and using the following syntax: <Directory "/Users/user/Sites/"> Options Indexes MultiViews SymLinks AllowOverride None Order allow,deny Allow from all </Directory> but nope, still doesn't work. I get a 403 error. If I try to symlink each individual file in instead of using a directory as a sub-directory, same error. Any help would be greatly appreciated! I'd just like to symlink directories into the ~/Sites one and browse them on my iOS device over wifi. I'm on OS X 10.7 Lion trying to connect with iOS 5.

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  • Subversion COPY/MOVE - File not found: transaction 'XXX-XX'

    - by theplatz
    I'm attempting to create a branch in one of my subversion repositories and keep running into an error. No mater what is done, I keep getting the following: File not found: transaction '3062-2e6', path '/Software/XXXXXX/branches/testbranch' I've noticed that the first part of the '3063-3e6' in the above message is the last successful committed revision in the repository. My apache logs don't give much more information: [Wed Nov 24 14:10:38 2010] [error] [client x.x.x.x] Could not MOVE/COPY /svn/p070361/!svn/bc/3049/Software/SXXXXXX/trunk. [404, #0] [Wed Nov 24 14:10:38 2010] [error] [client x.x.x.x] Unable to make a filesystem copy. [404, #160013] [Wed Nov 24 14:10:38 2010] [error] [client x.x.x.x] File not found: transaction '3059-2e2', path '/Software/XXXXXX/branches/testbranch' [404, #160013] This is all happening on a server with an nginx frontend that proxies to Apache for the subversion bits. Other repositories are able to branch fine and I was able to create the branch using file:/// from the command line on the server this is occurring on. The permissions on this repository match every other repository and disk space is not an issue.

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  • Migrate active directory to Google apps for business

    - by dewnix
    I've got a problem migrating active directory to Gapps. I'm stuck on google apps directory sync (GADS) where it just gives the error "java.lang.NullPointerException" after testing the connection during the LDAP configuration step. I checked the logs and I've pretty much determined that port 389 (standard LDAP port) isn't listening on the exchange server. I've tried telneting to it (from another machine in the same network) with no luck but I can telnet to other ports, that i know are open, successfully. I know they're open because I used portqry and netstat to see them. I'm suspecting that the active directory isn't even installed/running on this machine because there's no active directory services at all running on it. There's no active directory services that say they're NOT running either though. Is it possible AD is installed somewhere else? does it have to be on a machine inside the same network? I found the domain controller and it's host name and when I telnet with port 389, it works however GADS still gives me the same exact error when I substitute that server in. Actually, no matter what ridiculous settings i put into GADS, i still get that same NullPointer error. If i could get some different error than that NullPointer, i'd call that a successful day.

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  • Removing Phantom Registry Entries

    - by shedd
    First, some background: I'm trying to install an HP OfficeJet 6500. I've got the printer setup on my network fine, but the driver software installation on Windows XP (SP3) is a PITA. The installation program keeps dying with the following error: Product: Network -- Error 1324. The folder path 'WD Sync Data' contains an invalid character. WD Sync Data is a program on external Western Digital harddrives, which I used to use on this computer, but no external drive is current mounted. I've searched my registry for those keywords, but haven't found anything. I also ran CCleaner on the registry just to make sure, but no loose ends detected there, either. There are a number of Google results for the error, but no solutions. One post pointed me to the Windows Installer Cleanup Utility, but this utility doesn't even run - it dies with the same error before even starting. Any thoughts on where I could look to clean up this invalid character so I can get the HP installation wizard to successfully run? Many thanks in advance!

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  • MySQL InnoDB/socket issue on Mac OS X 10.6.4

    - by user55217
    I have an ongoing issue on my Macbook Pro OS X 10.6.4. Intermittently, my MySQL install will not create a socket on startup. Rebooting sometimes, but not always, solves the problem. Deleting the ib* files in /usr/local/mysql/data and then restarting sometimes, but not always, solves the problem. My error logs tell me the following: Plugin InnoDB init function returned error Plugin InnoDB registration as a STORAGE ENGINE failed Can't start server: Bind on TCP/IP port: Address already in use Do you already have another mysqld server running on port: 3306? Aborting It then appears to attempt to start again and generates this error 20 - 30 times: Unable to lock ./ibdata1, error 35 Check that you do not already have another mysqld process using the same InnoDB data or log files Though the socket file is not created, I can connect to my MySQL db directly over localhost. Although, this does not help me from a PHP standpoint. Any thoughts on what I can do to resolve the issue or debug further? I'm at a loss as to where to go from here.

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  • Subversion: Secure connection truncated

    - by Nick
    Hi, I'm trying to set-up a subversion server with apache2/webdav access. I've created the repository and configure Apache according to the official book, and I can see the repository in a webbrowser. The browser shows: conf/ db/ hooks/ locks/ Although clicking any of those links gives an empty xml document like: <D:error> <C:error/> <m:human-readable errcode="2"> Could not open the requested SVN filesystem </m:human-readable> </D:error> I've never used subversion before so I assume this is correct? Anyway, when I try to connect via a command line client, it asks for my password, I give it, then I get the (useless) error message: svn: OPTIONS of 'https://svn.mysite.com': Could not read status line: Secure connection truncated (https://svn.mysite.com) The command I'm using is: svn checkout https://svn.mysite.com/ svn.mysite.com Subversion was installed using Ubuntu's package manager. It's version 1.6.6 on Ubuntu 10.04. My Virtualhost Cofiguration: <VirtualHost 123.123.12.12:443> ServerAdmin [email protected] ServerName svn.mysite.com <Location /> DAV svn SVNParentPath /var/svn/repos SVNListParentPath On AuthType Basic AuthName "Subversion Repository" AuthUserFile /etc/subversion/passwd Require valid-user </Location> # Setup The SSL Certificate Paths SSLEngine On SSLCertificateFile /etc/ssl/certs/mysite.com.crt SSLCertificateKeyFile /etc/ssl/private/dmysite.com.key </VirtualHost>

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  • Is this DVD drive broken? Brand new, i need help convincing

    - by acidzombie24
    I am asking bc i know dell is going to give me a problem. How do i know if my DVD is broken on my laptop? i burnt 4 DL disc and they ALL failed, i called and dell suggested roxio. I used it and burnt 1 disc without error and the 2nd disc with an error. With both apps there were no 'problems' during the burning process only failed on the verification process. Some of these bad disc dont work on other PCs and one locks up windows when i click a specific file. Does that sound like a broken burner to you guys? when i called dell they told me since it can read disc properly 100% of the time and software doesnt fail in the burning process its not a broken drive _. They forward me to software support who demand a fee (i think $100) to help me fix my software. I am annoyed bc i dont want to be on the phone for them to watch me burn a dvd and since i burned it once correctly i dont want to happen to burn correctly again to have them say they solved my problem (doing nothing) and charge me refusing to refund. -edit- The errors i got were 1) the request could not be performed because of an I/O device error 2) Windows locking up when opening 1 specific file 3) Cannot copy : Data error (crc) NOTE: the file that causes the problems are random every disc

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  • Question marks showing in ls of directory. IO errors too.

    - by jaymoo
    Has anyone seen this before? I've got a raid 5 mounted on my server and for whatever reason it started showing this: jason@box2:/mnt/raid1/cra$ ls -alh ls: cannot access e6eacc985fea729b2d5bc74078632738: Input/output error ls: cannot access 257ad35ee0b12a714530c30dccf9210f: Input/output error total 0 drwxr-xr-x 5 root root 123 2009-08-19 16:33 . drwxr-xr-x 3 root root 16 2009-08-14 17:15 .. ?????????? ? ? ? ? ? 257ad35ee0b12a714530c30dccf9210f drwxr-xr-x 3 root root 57 2009-08-19 16:58 9c89a78e93ae6738e01136db9153361b ?????????? ? ? ? ? ? e6eacc985fea729b2d5bc74078632738 The md5 strings are actual directory names and not part of the error. The question marks are odd, and any directory with a question mark throws an io error when you attempt to use/delete/etc it. I was unable to umount the drive due to "busy". Rebooting the server "fixed" it but it was throwing some raid errors on shutdown. I have configured two raid 5 arrays and both started doing this on random files. Both are using the following config: mkfs.xfs -l size=128m -d agcount=32 mount -t xfs -o noatime,logbufs=8 Nothing too fancy, but part of an optimized config for this box. We're not partitioning the drives and that was suggested as a possible issue. Could this be the culprit?

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  • Debian boot problems

    - by psp
    I've got Debian server with one disk. No dual boot or anything fancy. Just Debian 6.0 (Squeeze). I rebooted the server today and now it doesn't boot. I get the following (from GRUB): error: hd0,msdos out of disk I then get a grub prompt grub rescue> I've been googling for ages with no luck. /etc/fstab > #/etc/fstab: static file system information. > # > # <file system> <mount point> <type> <options> <dump> <pass> > aufs / aufs rw 0 0 > tmpfs /tmp tmpfs nosuid,nodev 0 0 I've run debian rescue mode and looked through the syslog. I see hundreds of entries like this: Jun 30 22:51:08 kernel: [ 615.217382] sd 2:0:0:0: [sda] Unhandled error code Jun 30 22:51:08 kernel: [ 615.217385] sd 2:0:0:0: [sda] Result: hostbyte=DID_BAD_TARGET driverbyte=DRIVER_OK Jun 30 22:51:08 kernel: [ 615.217389] sd 2:0:0:0: [sda] CDB: Read(10): 28 00 00 00 00 00 00 00 08 00 Jun 30 22:51:08 kernel: [ 615.217399] end_request: I/O error, dev sda, logical block 0 Jun 30 22:51:08 kernel: [ 615.217402] Buffer I/O error on device sda, logical block 0

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  • $_POST data returns empty when headers are > POST_MAX_SIZE

    - by Jared
    Hi Hopefully someone here might have an answer to my question. I have a basic form that contains simple fields, like name, number, email address etc and 1 file upload field. I am trying to add some validation into my script that detects if the file is too large and then rejects the user back to the form to select/upload a smaller file. My problem is, if a user selects a file that is bigger than my validation file size rule and larger than php.ini POST_MAX_SIZE/UPLOAD_MAX_FILESIZE and pushes submit, then PHP seems to try process the form only to fail on the POST_MAX_SIZE settings and then clears the entire $_POST array and returns nothing back to the form. Is there a way around this? Surely if someone uploads something than the max size configured in the php.ini then you can still get the rest of the $_POST data??? Here is my code. <?php function validEmail($email) { $isValid = true; $atIndex = strrpos($email, "@"); if (is_bool($atIndex) && !$atIndex) { $isValid = false; } else { $domain = substr($email, $atIndex+1); $local = substr($email, 0, $atIndex); $localLen = strlen($local); $domainLen = strlen($domain); if ($localLen < 1 || $localLen > 64) { // local part length exceeded $isValid = false; } else if ($domainLen < 1 || $domainLen > 255) { // domain part length exceeded $isValid = false; } else if ($local[0] == '.' || $local[$localLen-1] == '.') { // local part starts or ends with '.' $isValid = false; } else if (preg_match('/\\.\\./', $local)) { // local part has two consecutive dots $isValid = false; } else if (!preg_match('/^[A-Za-z0-9\\-\\.]+$/', $domain)) { // character not valid in domain part $isValid = false; } else if (preg_match('/\\.\\./', $domain)) { // domain part has two consecutive dots $isValid = false; } else if (!preg_match('/^(\\\\.|[A-Za-z0-9!#%&`_=\\/$\'*+?^{}|~.-])+$/', str_replace("\\\\","",$local))) { // character not valid in local part unless // local part is quoted if (!preg_match('/^"(\\\\"|[^"])+"$/', str_replace("\\\\","",$local))) { $isValid = false; } } } return $isValid; } //setup post variables @$name = htmlspecialchars(trim($_REQUEST['name'])); @$emailCheck = htmlspecialchars(trim($_REQUEST['email'])); @$organisation = htmlspecialchars(trim($_REQUEST['organisation'])); @$title = htmlspecialchars(trim($_REQUEST['title'])); @$phone = htmlspecialchars(trim($_REQUEST['phone'])); @$location = htmlspecialchars(trim($_REQUEST['location'])); @$description = htmlspecialchars(trim($_REQUEST['description'])); @$fileError = 0; @$phoneError = ""; //setup file upload handler $target_path = 'uploads/'; $filename = basename( @$_FILES['uploadedfile']['name']); $max_size = 8000000; // maximum file size (8mb in bytes) NB: php.ini max filesize upload is 10MB on test environment. $allowed_filetypes = Array(".pdf", ".doc", ".zip", ".txt", ".xls", ".docx", ".csv", ".rtf"); //put extensions in here that should be uploaded only. $ext = substr($filename, strpos($filename,'.'), strlen($filename)-1); // Get the extension from the filename. if(!is_writable($target_path)) die('You cannot upload to the specified directory, please CHMOD it to 777.'); //Check if we can upload to the specified upload folder. //display form function function displayForm($name, $emailCheck, $organisation, $phone, $title, $location, $description, $phoneError, $allowed_filetypes, $ext, $filename, $fileError) { //make $emailCheck global so function can get value from global scope. global $emailCheck; global $max_size; echo '<form action="geodetic_form.php" method="post" name="contact" id="contact" enctype="multipart/form-data">'."\n". '<fieldset>'."\n".'<div>'."\n"; //name echo '<label for="name"><span class="mandatory">*</span>Your name:</label>'."\n". '<input type="text" name="name" id="name" class="inputText required" value="'. $name .'" />'."\n"; //check if name field is filled out if (isset($_REQUEST['submit']) && empty($name)) { echo '<label for="name" class="error">Please enter your name.</label>'."\n"; } echo '</div>'."\n". '<div>'."\n"; //Email echo '<label for="email"><span class="mandatory">*</span>Your email:</label>'."\n". '<input type="text" name="email" id="email" class="inputText required email" value="'. $emailCheck .'" />'."\n"; // check if email field is filled out and proper format if (isset($_REQUEST['submit']) && validEmail($emailCheck) == false) { echo '<label for="email" class="error">Invalid email address entered.</label>'."\n"; } echo '</div>'."\n". '<div>'."\n"; //organisation echo '<label for="phone">Organisation:</label>'."\n". '<input type="text" name="organisation" id="organisation" class="inputText" value="'. $organisation .'" />'."\n"; echo '</div>'."\n". '</fieldset>'."\n".'<fieldset>'. "\n" . '<div>'."\n"; //title echo '<label for="phone">Title:</label>'."\n". '<input type="text" name="title" id="title" class="inputText" value="'. $title .'" />'."\n"; echo '</div>'."\n". '</fieldset>'."\n".'<fieldset>'. "\n" . '<div>'."\n"; //phone echo '<label for="phone"><span class="mandatory">*</span>Phone <br /><span class="small">(include area code)</span>:</label>'."\n". '<input type="text" name="phone" id="phone" class="inputText required" value="'. $phone .'" />'."\n"; // check if phone field is filled out that it has numbers and not characters if (isset($_REQUEST['submit']) && $phoneError == "true" && empty($phone)) echo '<label for="email" class="error">Please enter a valid phone number.</label>'."\n"; echo '</div>'."\n". '</fieldset>'."\n".'<fieldset>'. "\n" . '<div>'."\n"; //Location echo '<label class="location" for="location"><span class="mandatory">*</span>Location:</label>'."\n". '<textarea name="location" id="location" class="required">'. $location .'</textarea>'."\n"; //check if message field is filled out if (isset($_REQUEST['submit']) && empty($_REQUEST['location'])) echo '<label for="location" class="error">This field is required.</label>'."\n"; echo '</div>'."\n". '</fieldset>'."\n".'<fieldset>'. "\n" . '<div>'."\n"; //description echo '<label class="description" for="description">Description:</label>'."\n". '<textarea name="description" id="queryComments">'. $description .'</textarea>'."\n"; echo '</div>'."\n". '</fieldset>'."\n".'<fieldset>'. "\n" . '<div>'."\n"; //file upload echo '<label class="uploadedfile" for="uploadedfile">File:</label>'."\n". '<input type="file" name="uploadedfile" id="uploadedfile" value="'. $filename .'" />'."\n"; // Check if the filetype is allowed, if not DIE and inform the user. switch ($fileError) { case "1": echo '<label for="uploadedfile" class="error">The file you attempted to upload is not allowed.</label>'; break; case "2": echo '<label for="uploadedfile" class="error">The file you attempted to upload is too large.</label>'; break; } echo '</div>'."\n". '</fieldset>'; //end of form echo '<div class="submit"><input type="submit" name="submit" value="Submit" id="submit" /></div>'. '<div class="clear"><p><br /></p></div>'; } //end function //setup error validations if (isset($_REQUEST['submit']) && !empty($_REQUEST['phone']) && !is_numeric($_REQUEST['phone'])) $phoneError = "true"; if (isset($_REQUEST['submit']) && $_FILES['uploadedfile']['error'] != 4 && !in_array($ext, $allowed_filetypes)) $fileError = 1; if (isset($_REQUEST['submit']) && $_FILES["uploadedfile"]["size"] > $max_size) $fileError = 2; echo "this condition " . $fileError; $POST_MAX_SIZE = ini_get('post_max_size'); $mul = substr($POST_MAX_SIZE, -1); $mul = ($mul == 'M' ? 1048576 : ($mul == 'K' ? 1024 : ($mul == 'G' ? 1073741824 : 1))); if ($_SERVER['CONTENT_LENGTH'] > $mul*(int)$POST_MAX_SIZE && $POST_MAX_SIZE) echo "too big!!"; echo $POST_MAX_SIZE; if(empty($name) || empty($phone) || empty($location) || validEmail($emailCheck) == false || $phoneError == "true" || $fileError != 0) { displayForm($name, $emailCheck, $organisation, $phone, $title, $location, $description, $phoneError, $allowed_filetypes, $ext, $filename, $fileError); echo $fileError; echo "max size is: " .$max_size; echo "and file size is: " . $_FILES["uploadedfile"]["size"]; exit; } else { //copy file from temp to upload directory $path_of_uploaded_file = $target_path . $filename; $tmp_path = $_FILES["uploadedfile"]["tmp_name"]; echo $tmp_path; echo "and file size is: " . filesize($_FILES["uploadedfile"]["tmp_name"]); exit; if(is_uploaded_file($tmp_path)) { if(!copy($tmp_path,$path_of_uploaded_file)) { echo 'error while copying the uploaded file'; } } //test debug stuff echo "sending email..."; exit; } ?> PHP is returning this error in the log: [29-Apr-2010 10:32:47] PHP Warning: POST Content-Length of 57885895 bytes exceeds the limit of 10485760 bytes in Unknown on line 0 Excuse all the debug stuff :) FTR, I am running PHP 5.1.2 on IIS. TIA Jared

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  • Problems extracting information from RSS feed description field

    - by Graeme
    Hi, I've built an iPhone application using the parsing code from the TopSongs sample iPhone application. I've hit a problem though - the feed I'm trying to parse data from doesn't have a separate field for every piece of information (i.e. if it was for a feed about dogs, all the information such as dog type, dog age and dog price is contained in the feed. However, the TopSongs app relies on information having its own tags, so instead of using it uses and . So my question is this. How do I extract this information from the description field so that it can be parsed using the TopSongs parser? Can you somehow extract the dog age, price and type information using Yahoo Pipes and use that RSS feed for the feed? Or is there code that I can add to do it in application? Update: To view the code of my application parser (based on the TopSongs Core Data Apple provided application, see below. Here's a sample of one item from the the actual RSS feed I'm using (the description is longer, and has status,size, and a couple of other fields, but they're all formatted the same.: <item> <title>MOE, MARGRET STREET</title> <description> <b>District/Region:</b>&nbsp;REGION 09</br><b>Location:</b>&nbsp;MOE</br><b>Name:</b>&nbsp;MARGRET STREET</br></description> <pubDate>Thu,11 Mar 2010 05:43:03 GMT</pubDate> <guid>1266148</guid> </item> /* File: iTunesRSSImporter.m Abstract: Downloads, parses, and imports the iTunes top songs RSS feed into Core Data. Version: 1.1 Disclaimer: IMPORTANT: This Apple software is supplied to you by Apple Inc. ("Apple") in consideration of your agreement to the following terms, and your use, installation, modification or redistribution of this Apple software constitutes acceptance of these terms. If you do not agree with these terms, please do not use, install, modify or redistribute this Apple software. In consideration of your agreement to abide by the following terms, and subject to these terms, Apple grants you a personal, non-exclusive license, under Apple's copyrights in this original Apple software (the "Apple Software"), to use, reproduce, modify and redistribute the Apple Software, with or without modifications, in source and/or binary forms; provided that if you redistribute the Apple Software in its entirety and without modifications, you must retain this notice and the following text and disclaimers in all such redistributions of the Apple Software. Neither the name, trademarks, service marks or logos of Apple Inc. may be used to endorse or promote products derived from the Apple Software without specific prior written permission from Apple. Except as expressly stated in this notice, no other rights or licenses, express or implied, are granted by Apple herein, including but not limited to any patent rights that may be infringed by your derivative works or by other works in which the Apple Software may be incorporated. The Apple Software is provided by Apple on an "AS IS" basis. APPLE MAKES NO WARRANTIES, EXPRESS OR IMPLIED, INCLUDING WITHOUT LIMITATION THE IMPLIED WARRANTIES OF NON-INFRINGEMENT, MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE, REGARDING THE APPLE SOFTWARE OR ITS USE AND OPERATION ALONE OR IN COMBINATION WITH YOUR PRODUCTS. IN NO EVENT SHALL APPLE BE LIABLE FOR ANY SPECIAL, INDIRECT, INCIDENTAL OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) ARISING IN ANY WAY OUT OF THE USE, REPRODUCTION, MODIFICATION AND/OR DISTRIBUTION OF THE APPLE SOFTWARE, HOWEVER CAUSED AND WHETHER UNDER THEORY OF CONTRACT, TORT (INCLUDING NEGLIGENCE), STRICT LIABILITY OR OTHERWISE, EVEN IF APPLE HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. Copyright (C) 2009 Apple Inc. All Rights Reserved. */ #import "iTunesRSSImporter.h" #import "Song.h" #import "Category.h" #import "CategoryCache.h" #import <libxml/tree.h> // Function prototypes for SAX callbacks. This sample implements a minimal subset of SAX callbacks. // Depending on your application's needs, you might want to implement more callbacks. static void startElementSAX(void *context, const xmlChar *localname, const xmlChar *prefix, const xmlChar *URI, int nb_namespaces, const xmlChar **namespaces, int nb_attributes, int nb_defaulted, const xmlChar **attributes); static void endElementSAX(void *context, const xmlChar *localname, const xmlChar *prefix, const xmlChar *URI); static void charactersFoundSAX(void *context, const xmlChar *characters, int length); static void errorEncounteredSAX(void *context, const char *errorMessage, ...); // Forward reference. The structure is defined in full at the end of the file. static xmlSAXHandler simpleSAXHandlerStruct; // Class extension for private properties and methods. @interface iTunesRSSImporter () @property BOOL storingCharacters; @property (nonatomic, retain) NSMutableData *characterBuffer; @property BOOL done; @property BOOL parsingASong; @property NSUInteger countForCurrentBatch; @property (nonatomic, retain) Song *currentSong; @property (nonatomic, retain) NSURLConnection *rssConnection; @property (nonatomic, retain) NSDateFormatter *dateFormatter; // The autorelease pool property is assign because autorelease pools cannot be retained. @property (nonatomic, assign) NSAutoreleasePool *importPool; @end static double lookuptime = 0; @implementation iTunesRSSImporter @synthesize iTunesURL, delegate, persistentStoreCoordinator; @synthesize rssConnection, done, parsingASong, storingCharacters, currentSong, countForCurrentBatch, characterBuffer, dateFormatter, importPool; - (void)dealloc { [iTunesURL release]; [characterBuffer release]; [currentSong release]; [rssConnection release]; [dateFormatter release]; [persistentStoreCoordinator release]; [insertionContext release]; [songEntityDescription release]; [theCache release]; [super dealloc]; } - (void)main { self.importPool = [[NSAutoreleasePool alloc] init]; if (delegate && [delegate respondsToSelector:@selector(importerDidSave:)]) { [[NSNotificationCenter defaultCenter] addObserver:delegate selector:@selector(importerDidSave:) name:NSManagedObjectContextDidSaveNotification object:self.insertionContext]; } done = NO; self.dateFormatter = [[[NSDateFormatter alloc] init] autorelease]; [dateFormatter setDateStyle:NSDateFormatterLongStyle]; [dateFormatter setTimeStyle:NSDateFormatterNoStyle]; // necessary because iTunes RSS feed is not localized, so if the device region has been set to other than US // the date formatter must be set to US locale in order to parse the dates [dateFormatter setLocale:[[[NSLocale alloc] initWithLocaleIdentifier:@"US"] autorelease]]; self.characterBuffer = [NSMutableData data]; NSURLRequest *theRequest = [NSURLRequest requestWithURL:iTunesURL]; // create the connection with the request and start loading the data rssConnection = [[NSURLConnection alloc] initWithRequest:theRequest delegate:self]; // This creates a context for "push" parsing in which chunks of data that are not "well balanced" can be passed // to the context for streaming parsing. The handler structure defined above will be used for all the parsing. // The second argument, self, will be passed as user data to each of the SAX handlers. The last three arguments // are left blank to avoid creating a tree in memory. context = xmlCreatePushParserCtxt(&simpleSAXHandlerStruct, self, NULL, 0, NULL); if (rssConnection != nil) { do { [[NSRunLoop currentRunLoop] runMode:NSDefaultRunLoopMode beforeDate:[NSDate distantFuture]]; } while (!done); } // Display the total time spent finding a specific object for a relationship NSLog(@"lookup time %f", lookuptime); // Release resources used only in this thread. xmlFreeParserCtxt(context); self.characterBuffer = nil; self.dateFormatter = nil; self.rssConnection = nil; self.currentSong = nil; [theCache release]; theCache = nil; NSError *saveError = nil; NSAssert1([insertionContext save:&saveError], @"Unhandled error saving managed object context in import thread: %@", [saveError localizedDescription]); if (delegate && [delegate respondsToSelector:@selector(importerDidSave:)]) { [[NSNotificationCenter defaultCenter] removeObserver:delegate name:NSManagedObjectContextDidSaveNotification object:self.insertionContext]; } if (self.delegate != nil && [self.delegate respondsToSelector:@selector(importerDidFinishParsingData:)]) { [self.delegate importerDidFinishParsingData:self]; } [importPool release]; self.importPool = nil; } - (NSManagedObjectContext *)insertionContext { if (insertionContext == nil) { insertionContext = [[NSManagedObjectContext alloc] init]; [insertionContext setPersistentStoreCoordinator:self.persistentStoreCoordinator]; } return insertionContext; } - (void)forwardError:(NSError *)error { if (self.delegate != nil && [self.delegate respondsToSelector:@selector(importer:didFailWithError:)]) { [self.delegate importer:self didFailWithError:error]; } } - (NSEntityDescription *)songEntityDescription { if (songEntityDescription == nil) { songEntityDescription = [[NSEntityDescription entityForName:@"Song" inManagedObjectContext:self.insertionContext] retain]; } return songEntityDescription; } - (CategoryCache *)theCache { if (theCache == nil) { theCache = [[CategoryCache alloc] init]; theCache.managedObjectContext = self.insertionContext; } return theCache; } - (Song *)currentSong { if (currentSong == nil) { currentSong = [[Song alloc] initWithEntity:self.songEntityDescription insertIntoManagedObjectContext:self.insertionContext]; } return currentSong; } #pragma mark NSURLConnection Delegate methods // Forward errors to the delegate. - (void)connection:(NSURLConnection *)connection didFailWithError:(NSError *)error { [self performSelectorOnMainThread:@selector(forwardError:) withObject:error waitUntilDone:NO]; // Set the condition which ends the run loop. done = YES; } // Called when a chunk of data has been downloaded. - (void)connection:(NSURLConnection *)connection didReceiveData:(NSData *)data { // Process the downloaded chunk of data. xmlParseChunk(context, (const char *)[data bytes], [data length], 0); } - (void)connectionDidFinishLoading:(NSURLConnection *)connection { // Signal the context that parsing is complete by passing "1" as the last parameter. xmlParseChunk(context, NULL, 0, 1); context = NULL; // Set the condition which ends the run loop. done = YES; } #pragma mark Parsing support methods static const NSUInteger kImportBatchSize = 20; - (void)finishedCurrentSong { parsingASong = NO; self.currentSong = nil; countForCurrentBatch++; // Periodically purge the autorelease pool and save the context. The frequency of this action may need to be tuned according to the // size of the objects being parsed. The goal is to keep the autorelease pool from growing too large, but // taking this action too frequently would be wasteful and reduce performance. if (countForCurrentBatch == kImportBatchSize) { [importPool release]; self.importPool = [[NSAutoreleasePool alloc] init]; NSError *saveError = nil; NSAssert1([insertionContext save:&saveError], @"Unhandled error saving managed object context in import thread: %@", [saveError localizedDescription]); countForCurrentBatch = 0; } } /* Character data is appended to a buffer until the current element ends. */ - (void)appendCharacters:(const char *)charactersFound length:(NSInteger)length { [characterBuffer appendBytes:charactersFound length:length]; } - (NSString *)currentString { // Create a string with the character data using UTF-8 encoding. UTF-8 is the default XML data encoding. NSString *currentString = [[[NSString alloc] initWithData:characterBuffer encoding:NSUTF8StringEncoding] autorelease]; [characterBuffer setLength:0]; return currentString; } @end #pragma mark SAX Parsing Callbacks // The following constants are the XML element names and their string lengths for parsing comparison. // The lengths include the null terminator, to ensure exact matches. static const char *kName_Item = "item"; static const NSUInteger kLength_Item = 5; static const char *kName_Title = "title"; static const NSUInteger kLength_Title = 6; static const char *kName_Category = "category"; static const NSUInteger kLength_Category = 9; static const char *kName_Itms = "itms"; static const NSUInteger kLength_Itms = 5; static const char *kName_Artist = "description"; static const NSUInteger kLength_Artist = 7; static const char *kName_Album = "description"; static const NSUInteger kLength_Album = 6; static const char *kName_ReleaseDate = "releasedate"; static const NSUInteger kLength_ReleaseDate = 12; /* This callback is invoked when the importer finds the beginning of a node in the XML. For this application, out parsing needs are relatively modest - we need only match the node name. An "item" node is a record of data about a song. In that case we create a new Song object. The other nodes of interest are several of the child nodes of the Song currently being parsed. For those nodes we want to accumulate the character data in a buffer. Some of the child nodes use a namespace prefix. */ static void startElementSAX(void *parsingContext, const xmlChar *localname, const xmlChar *prefix, const xmlChar *URI, int nb_namespaces, const xmlChar **namespaces, int nb_attributes, int nb_defaulted, const xmlChar **attributes) { iTunesRSSImporter *importer = (iTunesRSSImporter *)parsingContext; // The second parameter to strncmp is the name of the element, which we known from the XML schema of the feed. // The third parameter to strncmp is the number of characters in the element name, plus 1 for the null terminator. if (prefix == NULL && !strncmp((const char *)localname, kName_Item, kLength_Item)) { importer.parsingASong = YES; } else if (importer.parsingASong && ( (prefix == NULL && (!strncmp((const char *)localname, kName_Title, kLength_Title) || !strncmp((const char *)localname, kName_Category, kLength_Category))) || ((prefix != NULL && !strncmp((const char *)prefix, kName_Itms, kLength_Itms)) && (!strncmp((const char *)localname, kName_Artist, kLength_Artist) || !strncmp((const char *)localname, kName_Album, kLength_Album) || !strncmp((const char *)localname, kName_ReleaseDate, kLength_ReleaseDate))) )) { importer.storingCharacters = YES; } } /* This callback is invoked when the parse reaches the end of a node. At that point we finish processing that node, if it is of interest to us. For "item" nodes, that means we have completed parsing a Song object. We pass the song to a method in the superclass which will eventually deliver it to the delegate. For the other nodes we care about, this means we have all the character data. The next step is to create an NSString using the buffer contents and store that with the current Song object. */ static void endElementSAX(void *parsingContext, const xmlChar *localname, const xmlChar *prefix, const xmlChar *URI) { iTunesRSSImporter *importer = (iTunesRSSImporter *)parsingContext; if (importer.parsingASong == NO) return; if (prefix == NULL) { if (!strncmp((const char *)localname, kName_Item, kLength_Item)) { [importer finishedCurrentSong]; } else if (!strncmp((const char *)localname, kName_Title, kLength_Title)) { importer.currentSong.title = importer.currentString; } else if (!strncmp((const char *)localname, kName_Category, kLength_Category)) { double before = [NSDate timeIntervalSinceReferenceDate]; Category *category = [importer.theCache categoryWithName:importer.currentString]; double delta = [NSDate timeIntervalSinceReferenceDate] - before; lookuptime += delta; importer.currentSong.category = category; } } else if (!strncmp((const char *)prefix, kName_Itms, kLength_Itms)) { if (!strncmp((const char *)localname, kName_Artist, kLength_Artist)) { NSString *string = importer.currentSong.artist; NSArray *strings = [string componentsSeparatedByString: @", "]; //importer.currentSong.artist = importer.currentString; } else if (!strncmp((const char *)localname, kName_Album, kLength_Album)) { importer.currentSong.album = importer.currentString; } else if (!strncmp((const char *)localname, kName_ReleaseDate, kLength_ReleaseDate)) { NSString *dateString = importer.currentString; importer.currentSong.releaseDate = [importer.dateFormatter dateFromString:dateString]; } } importer.storingCharacters = NO; } /* This callback is invoked when the parser encounters character data inside a node. The importer class determines how to use the character data. */ static void charactersFoundSAX(void *parsingContext, const xmlChar *characterArray, int numberOfCharacters) { iTunesRSSImporter *importer = (iTunesRSSImporter *)parsingContext; // A state variable, "storingCharacters", is set when nodes of interest begin and end. // This determines whether character data is handled or ignored. if (importer.storingCharacters == NO) return; [importer appendCharacters:(const char *)characterArray length:numberOfCharacters]; } /* A production application should include robust error handling as part of its parsing implementation. The specifics of how errors are handled depends on the application. */ static void errorEncounteredSAX(void *parsingContext, const char *errorMessage, ...) { // Handle errors as appropriate for your application. NSCAssert(NO, @"Unhandled error encountered during SAX parse."); } // The handler struct has positions for a large number of callback functions. If NULL is supplied at a given position, // that callback functionality won't be used. Refer to libxml documentation at http://www.xmlsoft.org for more information // about the SAX callbacks. static xmlSAXHandler simpleSAXHandlerStruct = { NULL, /* internalSubset */ NULL, /* isStandalone */ NULL, /* hasInternalSubset */ NULL, /* hasExternalSubset */ NULL, /* resolveEntity */ NULL, /* getEntity */ NULL, /* entityDecl */ NULL, /* notationDecl */ NULL, /* attributeDecl */ NULL, /* elementDecl */ NULL, /* unparsedEntityDecl */ NULL, /* setDocumentLocator */ NULL, /* startDocument */ NULL, /* endDocument */ NULL, /* startElement*/ NULL, /* endElement */ NULL, /* reference */ charactersFoundSAX, /* characters */ NULL, /* ignorableWhitespace */ NULL, /* processingInstruction */ NULL, /* comment */ NULL, /* warning */ errorEncounteredSAX, /* error */ NULL, /* fatalError //: unused error() get all the errors */ NULL, /* getParameterEntity */ NULL, /* cdataBlock */ NULL, /* externalSubset */ XML_SAX2_MAGIC, // NULL, startElementSAX, /* startElementNs */ endElementSAX, /* endElementNs */ NULL, /* serror */ }; Thanks.

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  • Installing Matlab on ubuntu 12.04 32 bits

    - by Amir
    I have been trying to install Matlab2012a, matlab2012b and Matlab2013a for like 4 hours, triedto fix my prospective errors regarding the posts 2012a, Ubuntu-Matlab Documentation and Matlab-central. But either i am recieving an error while the installation GUI pops-up with the error : The application encountered an unexpected error and needs to close. You may want to try re-installing your product(s). More information can be found at /tmp/mathworks_amir.log On the other hand for 2012a. and the errors for 2012b and 2013a is : `Installing ... Exception in thread "main" com.google.inject.ProvisionException: Guice provision errors: 1) Error in custom provider, java.lang.RuntimeException: java.lang.reflect.InvocationTargetException at com.mathworks.wizard.WizardModule.provideDisplayProperties(WizardModule.java:60) while locating com.mathworks.instutil.DisplayProperties at com.mathworks.wizard.ui.components.ComponentsModule.providePaintStrategy(ComponentsModule.java:76) while locating com.mathworks.wizard.ui.components.PaintStrategy for parameter 4 at com.mathworks.wizard.ui.components.SwingComponentFactoryImpl.(SwingComponentFactoryImpl.java:110) while locating com.mathworks.wizard.ui.components.SwingComponentFactoryImpl while locating com.mathworks.wizard.ui.components.SwingComponentFactory for parameter 1 at com.mathworks.wizard.ui.WizardUIImpl.(WizardUIImpl.java:65) while locating com.mathworks.wizard.ui.WizardUIImpl while locating com.mathworks.wizard.ui.WizardUI annotated with @com.google.inject.name.Named(value=BaseWizardUI) at com.mathworks.wizard.ui.UIModule.provideWizardUI(UIModule.java:50) while locating com.mathworks.wizard.ui.WizardUI for parameter 0 at com.mathworks.wizard.ExceptionHandlerImpl.(ExceptionHandlerImpl.java:22) while locating com.mathworks.wizard.ExceptionHandlerImpl while locating com.mathworks.wizard.ExceptionHandler 1 error at com.google.inject.InjectorImpl$4.get(InjectorImpl.java:767) at com.google.inject.InjectorImpl.getInstance(InjectorImpl.java:793) at com.mathworks.wizard.WizardLauncher.startWizard(WizardLauncher.java:160) at com.mathworks.wizard.WizardLauncher.start(WizardLauncher.java:75) at com.mathworks.wizard.AbstractLauncher.launch(AbstractLauncher.java:27) at com.mathworks.wizard.AbstractLauncher.launchStandalone(AbstractLauncher.java:18) at com.mathworks.professionalinstaller.Launcher.main(Launcher.java:21) Caused by: java.lang.RuntimeException: java.lang.reflect.InvocationTargetException at com.google.inject.internal.ProviderMethod.get(ProviderMethod.java:106) at com.google.inject.InternalFactoryToProviderAdapter.get(InternalFactoryToProviderAdapter.java:48) at com.google.inject.InjectorImpl$4$1.call(InjectorImpl.java:758) at com.google.inject.InjectorImpl.callInContext(InjectorImpl.java:811) at com.google.inject.InjectorImpl$4.get(InjectorImpl.java:754) at com.google.inject.spi.ProviderLookup$1.get(ProviderLookup.java:89) at com.google.inject.spi.ProviderLookup$1.get(ProviderLookup.java:89) at com.google.inject.internal.ProviderMethod.get(ProviderMethod.java:95) at com.google.inject.InternalFactoryToProviderAdapter.get(InternalFactoryToProviderAdapter.java:48) at com.google.inject.SingleParameterInjector.inject(SingleParameterInjector.java:42) at com.google.inject.SingleParameterInjector.getAll(SingleParameterInjector.java:66) at com.google.inject.ConstructorInjector.construct(ConstructorInjector.java:84) at com.google.inject.ConstructorBindingImpl$Factory.get(ConstructorBindingImpl.java:111) at com.google.inject.FactoryProxy.get(FactoryProxy.java:56) at com.google.inject.SingleParameterInjector.inject(SingleParameterInjector.java:42) at com.google.inject.SingleParameterInjector.getAll(SingleParameterInjector.java:66) at com.google.inject.ConstructorInjector.construct(ConstructorInjector.java:84) at com.google.inject.ConstructorBindingImpl$Factory.get(ConstructorBindingImpl.java:111) at com.google.inject.FactoryProxy.get(FactoryProxy.java:56) at com.google.inject.ProviderToInternalFactoryAdapter$1.call(ProviderToInternalFactoryAdapter.java:45) at com.google.inject.InjectorImpl.callInContext(InjectorImpl.java:811) at com.google.inject.ProviderToInternalFactoryAdapter.get(ProviderToInternalFactoryAdapter.java:42) at com.google.inject.Scopes$1$1.get(Scopes.java:54) at com.google.inject.InternalFactoryToProviderAdapter.get(InternalFactoryToProviderAdapter.java:48) at com.google.inject.InjectorImpl$4$1.call(InjectorImpl.java:758) at com.google.inject.InjectorImpl.callInContext(InjectorImpl.java:811) at com.google.inject.InjectorImpl$4.get(InjectorImpl.java:754) at com.google.inject.spi.ProviderLookup$1.get(ProviderLookup.java:89) at com.google.inject.spi.ProviderLookup$1.get(ProviderLookup.java:89) at com.google.inject.internal.ProviderMethod.get(ProviderMethod.java:95) at com.google.inject.InternalFactoryToProviderAdapter.get(InternalFactoryToProviderAdapter.java:48) at com.google.inject.ProviderToInternalFactoryAdapter$1.call(ProviderToInternalFactoryAdapter.java:45) at com.google.inject.InjectorImpl.callInContext(InjectorImpl.java:811) at com.google.inject.ProviderToInternalFactoryAdapter.get(ProviderToInternalFactoryAdapter.java:42) at com.google.inject.Scopes$1$1.get(Scopes.java:54) at com.google.inject.InternalFactoryToProviderAdapter.get(InternalFactoryToProviderAdapter.java:48) at com.google.inject.SingleParameterInjector.inject(SingleParameterInjector.java:42) at com.google.inject.SingleParameterInjector.getAll(SingleParameterInjector.java:66) at com.google.inject.ConstructorInjector.construct(ConstructorInjector.java:84) at com.google.inject.ConstructorBindingImpl$Factory.get(ConstructorBindingImpl.java:111) at com.google.inject.FactoryProxy.get(FactoryProxy.java:56) at com.google.inject.ProviderToInternalFactoryAdapter$1.call(ProviderToInternalFactoryAdapter.java:45) at com.google.inject.InjectorImpl.callInContext(InjectorImpl.java:811) at com.google.inject.ProviderToInternalFactoryAdapter.get(ProviderToInternalFactoryAdapter.java:42) at com.google.inject.Scopes$1$1.get(Scopes.java:54) at com.google.inject.InternalFactoryToProviderAdapter.get(InternalFactoryToProviderAdapter.java:48) at com.google.inject.InjectorImpl$4$1.call(InjectorImpl.java:758) at com.google.inject.InjectorImpl.callInContext(InjectorImpl.java:804) at com.google.inject.InjectorImpl$4.get(InjectorImpl.java:754) ... 6 more Caused by: java.lang.reflect.InvocationTargetException at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.lang.reflect.Method.invoke(Method.java:606) at com.google.inject.internal.ProviderMethod.get(ProviderMethod.java:101) ... 54 more Caused by: com.mathworks.instutil.JNIException: java.lang.UnsatisfiedLinkError: Can't load library: /tmp/mathworks_7417/bin/glnxa64/libinstutil.so at com.mathworks.instutil.NativeUtility.loadNativeLibrary(NativeUtility.java:39) at com.mathworks.instutil.NativeUtility.(NativeUtility.java:24) at com.mathworks.instutil.DisplayPropertiesImpl.(DisplayPropertiesImpl.java:10) at com.mathworks.wizard.WizardModule.provideDisplayProperties(WizardModule.java:67) ... 59 more Caused by: java.lang.UnsatisfiedLinkError: Can't load library: /tmp/mathworks_7417/bin/glnxa64/libinstutil.so at java.lang.ClassLoader.loadLibrary(ClassLoader.java:1842) at java.lang.Runtime.load0(Runtime.java:795) at java.lang.System.load(System.java:1061) at com.mathworks.instutil.NativeUtility.loadNativeLibrary(NativeUtility.java:37) ... 62 more Finished ` I have tried to 1- re-install java run-time 6 and then 7. 2- pass the java-path to the install with : -javadir 3- use the force to install on 32 bits as : sh install -glnx86 -v -javadir /usr/lib/jvm/java-7-openjdk-i386/jre But it seems none of them have worked so far. any ideas ??

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  • Using BPEL Performance Statistics to Diagnose Performance Bottlenecks

    - by fip
    Tuning performance of Oracle SOA 11G applications could be challenging. Because SOA is a platform for you to build composite applications that connect many applications and "services", when the overall performance is slow, the bottlenecks could be anywhere in the system: the applications/services that SOA connects to, the infrastructure database, or the SOA server itself.How to quickly identify the bottleneck becomes crucial in tuning the overall performance. Fortunately, the BPEL engine in Oracle SOA 11G (and 10G, for that matter) collects BPEL Engine Performance Statistics, which show the latencies of low level BPEL engine activities. The BPEL engine performance statistics can make it a bit easier for you to identify the performance bottleneck. Although the BPEL engine performance statistics are always available, the access to and interpretation of them are somewhat obscure in the early and current (PS5) 11G versions. This blog attempts to offer instructions that help you to enable, retrieve and interpret the performance statistics, before the future versions provides a more pleasant user experience. Overview of BPEL Engine Performance Statistics  SOA BPEL has a feature of collecting some performance statistics and store them in memory. One MBean attribute, StatLastN, configures the size of the memory buffer to store the statistics. This memory buffer is a "moving window", in a way that old statistics will be flushed out by the new if the amount of data exceeds the buffer size. Since the buffer size is limited by StatLastN, impacts of statistics collection on performance is minimal. By default StatLastN=-1, which means no collection of performance data. Once the statistics are collected in the memory buffer, they can be retrieved via another MBean oracle.as.soainfra.bpel:Location=[Server Name],name=BPELEngine,type=BPELEngine.> My friend in Oracle SOA development wrote this simple 'bpelstat' web app that looks up and retrieves the performance data from the MBean and displays it in a human readable form. It does not have beautiful UI but it is fairly useful. Although in Oracle SOA 11.1.1.5 onwards the same statistics can be viewed via a more elegant UI under "request break down" at EM -> SOA Infrastructure -> Service Engines -> BPEL -> Statistics, some unsophisticated minds like mine may still prefer the simplicity of the 'bpelstat' JSP. One thing that simple JSP does do well is that you can save the page and send it to someone to further analyze Follows are the instructions of how to install and invoke the BPEL statistic JSP. My friend in SOA Development will soon blog about interpreting the statistics. Stay tuned. Step1: Enable BPEL Engine Statistics for Each SOA Servers via Enterprise Manager First st you need to set the StatLastN to some number as a way to enable the collection of BPEL Engine Performance Statistics EM Console -> soa-infra(Server Name) -> SOA Infrastructure -> SOA Administration -> BPEL Properties Click on "More BPEL Configuration Properties" Click on attribute "StatLastN", set its value to some integer number. Typically you want to set it 1000 or more. Step 2: Download and Deploy bpelstat.war File to Admin Server, Note: the WAR file contains a JSP that does NOT have any security restriction. You do NOT want to keep in your production server for a long time as it is a security hazard. Deactivate the war once you are done. Download the bpelstat.war to your local PC At WebLogic Console, Go to Deployments -> Install Click on the "upload your file(s)" Click the "Browse" button to upload the deployment to Admin Server Accept the uploaded file as the path, click next Check the default option "Install this deployment as an application" Check "AdminServer" as the target server Finish the rest of the deployment with default settings Console -> Deployments Check the box next to "bpelstat" application Click on the "Start" button. It will change the state of the app from "prepared" to "active" Step 3: Invoke the BPEL Statistic Tool The BPELStat tool merely call the MBean of BPEL server and collects and display the in-memory performance statics. You usually want to do that after some peak loads. Go to http://<admin-server-host>:<admin-server-port>/bpelstat Enter the correct admin hostname, port, username and password Enter the SOA Server Name from which you want to collect the performance statistics. For example, SOA_MS1, etc. Click Submit Keep doing the same for all SOA servers. Step 3: Interpret the BPEL Engine Statistics You will see a few categories of BPEL Statistics from the JSP Page. First it starts with the overall latency of BPEL processes, grouped by synchronous and asynchronous processes. Then it provides the further break down of the measurements through the life time of a BPEL request, which is called the "request break down". 1. Overall latency of BPEL processes The top of the page shows that the elapse time of executing the synchronous process TestSyncBPELProcess from the composite TestComposite averages at about 1543.21ms, while the elapse time of executing the asynchronous process TestAsyncBPELProcess from the composite TestComposite2 averages at about 1765.43ms. The maximum and minimum latency were also shown. Synchronous process statistics <statistics>     <stats key="default/TestComposite!2.0.2-ScopedJMSOSB*soa_bfba2527-a9ba-41a7-95c5-87e49c32f4ff/TestSyncBPELProcess" min="1234" max="4567" average="1543.21" count="1000">     </stats> </statistics> Asynchronous process statistics <statistics>     <stats key="default/TestComposite2!2.0.2-ScopedJMSOSB*soa_bfba2527-a9ba-41a7-95c5-87e49c32f4ff/TestAsyncBPELProcess" min="2234" max="3234" average="1765.43" count="1000">     </stats> </statistics> 2. Request break down Under the overall latency categorized by synchronous and asynchronous processes is the "Request breakdown". Organized by statistic keys, the Request breakdown gives finer grain performance statistics through the life time of the BPEL requests.It uses indention to show the hierarchy of the statistics. Request breakdown <statistics>     <stats key="eng-composite-request" min="0" max="0" average="0.0" count="0">         <stats key="eng-single-request" min="22" max="606" average="258.43" count="277">             <stats key="populate-context" min="0" max="0" average="0.0" count="248"> Please note that in SOA 11.1.1.6, the statistics under Request breakdown is aggregated together cross all the BPEL processes based on statistic keys. It does not differentiate between BPEL processes. If two BPEL processes happen to have the statistic that share same statistic key, the statistics from two BPEL processes will be aggregated together. Keep this in mind when we go through more details below. 2.1 BPEL process activity latencies A very useful measurement in the Request Breakdown is the performance statistics of the BPEL activities you put in your BPEL processes: Assign, Invoke, Receive, etc. The names of the measurement in the JSP page directly come from the names to assign to each BPEL activity. These measurements are under the statistic key "actual-perform" Example 1:  Follows is the measurement for BPEL activity "AssignInvokeCreditProvider_Input", which looks like the Assign activity in a BPEL process that assign an input variable before passing it to the invocation:                                <stats key="AssignInvokeCreditProvider_Input" min="1" max="8" average="1.9" count="153">                                     <stats key="sensor-send-activity-data" min="0" max="1" average="0.0" count="306">                                     </stats>                                     <stats key="sensor-send-variable-data" min="0" max="0" average="0.0" count="153">                                     </stats>                                     <stats key="monitor-send-activity-data" min="0" max="0" average="0.0" count="306">                                     </stats>                                 </stats> Note: because as previously mentioned that the statistics cross all BPEL processes are aggregated together based on statistic keys, if two BPEL processes happen to name their Invoke activity the same name, they will show up at one measurement (i.e. statistic key). Example 2: Follows is the measurement of BPEL activity called "InvokeCreditProvider". You can not only see that by average it takes 3.31ms to finish this call (pretty fast) but also you can see from the further break down that most of this 3.31 ms was spent on the "invoke-service".                                  <stats key="InvokeCreditProvider" min="1" max="13" average="3.31" count="153">                                     <stats key="initiate-correlation-set-again" min="0" max="0" average="0.0" count="153">                                     </stats>                                     <stats key="invoke-service" min="1" max="13" average="3.08" count="153">                                         <stats key="prep-call" min="0" max="1" average="0.04" count="153">                                         </stats>                                     </stats>                                     <stats key="initiate-correlation-set" min="0" max="0" average="0.0" count="153">                                     </stats>                                     <stats key="sensor-send-activity-data" min="0" max="0" average="0.0" count="306">                                     </stats>                                     <stats key="sensor-send-variable-data" min="0" max="0" average="0.0" count="153">                                     </stats>                                     <stats key="monitor-send-activity-data" min="0" max="0" average="0.0" count="306">                                     </stats>                                     <stats key="update-audit-trail" min="0" max="2" average="0.03" count="153">                                     </stats>                                 </stats> 2.2 BPEL engine activity latency Another type of measurements under Request breakdown are the latencies of underlying system level engine activities. These activities are not directly tied to a particular BPEL process or process activity, but they are critical factors in the overall engine performance. These activities include the latency of saving asynchronous requests to database, and latency of process dehydration. My friend Malkit Bhasin is working on providing more information on interpreting the statistics on engine activities on his blog (https://blogs.oracle.com/malkit/). I will update this blog once the information becomes available. Update on 2012-10-02: My friend Malkit Bhasin has published the detail interpretation of the BPEL service engine statistics at his blog http://malkit.blogspot.com/2012/09/oracle-bpel-engine-soa-suite.html.

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  • Toorcon 15 (2013)

    - by danx
    The Toorcon gang (senior staff): h1kari (founder), nfiltr8, and Geo Introduction to Toorcon 15 (2013) A Tale of One Software Bypass of MS Windows 8 Secure Boot Breaching SSL, One Byte at a Time Running at 99%: Surviving an Application DoS Security Response in the Age of Mass Customized Attacks x86 Rewriting: Defeating RoP and other Shinanighans Clowntown Express: interesting bugs and running a bug bounty program Active Fingerprinting of Encrypted VPNs Making Attacks Go Backwards Mask Your Checksums—The Gorry Details Adventures with weird machines thirty years after "Reflections on Trusting Trust" Introduction to Toorcon 15 (2013) Toorcon 15 is the 15th annual security conference held in San Diego. I've attended about a third of them and blogged about previous conferences I attended here starting in 2003. As always, I've only summarized the talks I attended and interested me enough to write about them. Be aware that I may have misrepresented the speaker's remarks and that they are not my remarks or opinion, or those of my employer, so don't quote me or them. Those seeking further details may contact the speakers directly or use The Google. For some talks, I have a URL for further information. A Tale of One Software Bypass of MS Windows 8 Secure Boot Andrew Furtak and Oleksandr Bazhaniuk Yuri Bulygin, Oleksandr ("Alex") Bazhaniuk, and (not present) Andrew Furtak Yuri and Alex talked about UEFI and Bootkits and bypassing MS Windows 8 Secure Boot, with vendor recommendations. They previously gave this talk at the BlackHat 2013 conference. MS Windows 8 Secure Boot Overview UEFI (Unified Extensible Firmware Interface) is interface between hardware and OS. UEFI is processor and architecture independent. Malware can replace bootloader (bootx64.efi, bootmgfw.efi). Once replaced can modify kernel. Trivial to replace bootloader. Today many legacy bootkits—UEFI replaces them most of them. MS Windows 8 Secure Boot verifies everything you load, either through signatures or hashes. UEFI firmware relies on secure update (with signed update). You would think Secure Boot would rely on ROM (such as used for phones0, but you can't do that for PCs—PCs use writable memory with signatures DXE core verifies the UEFI boat loader(s) OS Loader (winload.efi, winresume.efi) verifies the OS kernel A chain of trust is established with a root key (Platform Key, PK), which is a cert belonging to the platform vendor. Key Exchange Keys (KEKs) verify an "authorized" database (db), and "forbidden" database (dbx). X.509 certs with SHA-1/SHA-256 hashes. Keys are stored in non-volatile (NV) flash-based NVRAM. Boot Services (BS) allow adding/deleting keys (can't be accessed once OS starts—which uses Run-Time (RT)). Root cert uses RSA-2048 public keys and PKCS#7 format signatures. SecureBoot — enable disable image signature checks SetupMode — update keys, self-signed keys, and secure boot variables CustomMode — allows updating keys Secure Boot policy settings are: always execute, never execute, allow execute on security violation, defer execute on security violation, deny execute on security violation, query user on security violation Attacking MS Windows 8 Secure Boot Secure Boot does NOT protect from physical access. Can disable from console. Each BIOS vendor implements Secure Boot differently. There are several platform and BIOS vendors. It becomes a "zoo" of implementations—which can be taken advantage of. Secure Boot is secure only when all vendors implement it correctly. Allow only UEFI firmware signed updates protect UEFI firmware from direct modification in flash memory protect FW update components program SPI controller securely protect secure boot policy settings in nvram protect runtime api disable compatibility support module which allows unsigned legacy Can corrupt the Platform Key (PK) EFI root certificate variable in SPI flash. If PK is not found, FW enters setup mode wich secure boot turned off. Can also exploit TPM in a similar manner. One is not supposed to be able to directly modify the PK in SPI flash from the OS though. But they found a bug that they can exploit from User Mode (undisclosed) and demoed the exploit. It loaded and ran their own bootkit. The exploit requires a reboot. Multiple vendors are vulnerable. They will disclose this exploit to vendors in the future. Recommendations: allow only signed updates protect UEFI fw in ROM protect EFI variable store in ROM Breaching SSL, One Byte at a Time Yoel Gluck and Angelo Prado Angelo Prado and Yoel Gluck, Salesforce.com CRIME is software that performs a "compression oracle attack." This is possible because the SSL protocol doesn't hide length, and because SSL compresses the header. CRIME requests with every possible character and measures the ciphertext length. Look for the plaintext which compresses the most and looks for the cookie one byte-at-a-time. SSL Compression uses LZ77 to reduce redundancy. Huffman coding replaces common byte sequences with shorter codes. US CERT thinks the SSL compression problem is fixed, but it isn't. They convinced CERT that it wasn't fixed and they issued a CVE. BREACH, breachattrack.com BREACH exploits the SSL response body (Accept-Encoding response, Content-Encoding). It takes advantage of the fact that the response is not compressed. BREACH uses gzip and needs fairly "stable" pages that are static for ~30 seconds. It needs attacker-supplied content (say from a web form or added to a URL parameter). BREACH listens to a session's requests and responses, then inserts extra requests and responses. Eventually, BREACH guesses a session's secret key. Can use compression to guess contents one byte at-a-time. For example, "Supersecret SupersecreX" (a wrong guess) compresses 10 bytes, and "Supersecret Supersecret" (a correct guess) compresses 11 bytes, so it can find each character by guessing every character. To start the guess, BREACH needs at least three known initial characters in the response sequence. Compression length then "leaks" information. Some roadblocks include no winners (all guesses wrong) or too many winners (multiple possibilities that compress the same). The solutions include: lookahead (guess 2 or 3 characters at-a-time instead of 1 character). Expensive rollback to last known conflict check compression ratio can brute-force first 3 "bootstrap" characters, if needed (expensive) block ciphers hide exact plain text length. Solution is to align response in advance to block size Mitigations length: use variable padding secrets: dynamic CSRF tokens per request secret: change over time separate secret to input-less servlets Future work eiter understand DEFLATE/GZIP HTTPS extensions Running at 99%: Surviving an Application DoS Ryan Huber Ryan Huber, Risk I/O Ryan first discussed various ways to do a denial of service (DoS) attack against web services. One usual method is to find a slow web page and do several wgets. Or download large files. Apache is not well suited at handling a large number of connections, but one can put something in front of it Can use Apache alternatives, such as nginx How to identify malicious hosts short, sudden web requests user-agent is obvious (curl, python) same url requested repeatedly no web page referer (not normal) hidden links. hide a link and see if a bot gets it restricted access if not your geo IP (unless the website is global) missing common headers in request regular timing first seen IP at beginning of attack count requests per hosts (usually a very large number) Use of captcha can mitigate attacks, but you'll lose a lot of genuine users. Bouncer, goo.gl/c2vyEc and www.github.com/rawdigits/Bouncer Bouncer is software written by Ryan in netflow. Bouncer has a small, unobtrusive footprint and detects DoS attempts. It closes blacklisted sockets immediately (not nice about it, no proper close connection). Aggregator collects requests and controls your web proxies. Need NTP on the front end web servers for clean data for use by bouncer. Bouncer is also useful for a popularity storm ("Slashdotting") and scraper storms. Future features: gzip collection data, documentation, consumer library, multitask, logging destroyed connections. Takeaways: DoS mitigation is easier with a complete picture Bouncer designed to make it easier to detect and defend DoS—not a complete cure Security Response in the Age of Mass Customized Attacks Peleus Uhley and Karthik Raman Peleus Uhley and Karthik Raman, Adobe ASSET, blogs.adobe.com/asset/ Peleus and Karthik talked about response to mass-customized exploits. Attackers behave much like a business. "Mass customization" refers to concept discussed in the book Future Perfect by Stan Davis of Harvard Business School. Mass customization is differentiating a product for an individual customer, but at a mass production price. For example, the same individual with a debit card receives basically the same customized ATM experience around the world. Or designing your own PC from commodity parts. Exploit kits are another example of mass customization. The kits support multiple browsers and plugins, allows new modules. Exploit kits are cheap and customizable. Organized gangs use exploit kits. A group at Berkeley looked at 77,000 malicious websites (Grier et al., "Manufacturing Compromise: The Emergence of Exploit-as-a-Service", 2012). They found 10,000 distinct binaries among them, but derived from only a dozen or so exploit kits. Characteristics of Mass Malware: potent, resilient, relatively low cost Technical characteristics: multiple OS, multipe payloads, multiple scenarios, multiple languages, obfuscation Response time for 0-day exploits has gone down from ~40 days 5 years ago to about ~10 days now. So the drive with malware is towards mass customized exploits, to avoid detection There's plenty of evicence that exploit development has Project Manager bureaucracy. They infer from the malware edicts to: support all versions of reader support all versions of windows support all versions of flash support all browsers write large complex, difficult to main code (8750 lines of JavaScript for example Exploits have "loose coupling" of multipe versions of software (adobe), OS, and browser. This allows specific attacks against specific versions of multiple pieces of software. Also allows exploits of more obscure software/OS/browsers and obscure versions. Gave examples of exploits that exploited 2, 3, 6, or 14 separate bugs. However, these complete exploits are more likely to be buggy or fragile in themselves and easier to defeat. Future research includes normalizing malware and Javascript. Conclusion: The coming trend is that mass-malware with mass zero-day attacks will result in mass customization of attacks. x86 Rewriting: Defeating RoP and other Shinanighans Richard Wartell Richard Wartell The attack vector we are addressing here is: First some malware causes a buffer overflow. The malware has no program access, but input access and buffer overflow code onto stack Later the stack became non-executable. The workaround malware used was to write a bogus return address to the stack jumping to malware Later came ASLR (Address Space Layout Randomization) to randomize memory layout and make addresses non-deterministic. The workaround malware used was to jump t existing code segments in the program that can be used in bad ways "RoP" is Return-oriented Programming attacks. RoP attacks use your own code and write return address on stack to (existing) expoitable code found in program ("gadgets"). Pinkie Pie was paid $60K last year for a RoP attack. One solution is using anti-RoP compilers that compile source code with NO return instructions. ASLR does not randomize address space, just "gadgets". IPR/ILR ("Instruction Location Randomization") randomizes each instruction with a virtual machine. Richard's goal was to randomize a binary with no source code access. He created "STIR" (Self-Transofrming Instruction Relocation). STIR disassembles binary and operates on "basic blocks" of code. The STIR disassembler is conservative in what to disassemble. Each basic block is moved to a random location in memory. Next, STIR writes new code sections with copies of "basic blocks" of code in randomized locations. The old code is copied and rewritten with jumps to new code. the original code sections in the file is marked non-executible. STIR has better entropy than ASLR in location of code. Makes brute force attacks much harder. STIR runs on MS Windows (PEM) and Linux (ELF). It eliminated 99.96% or more "gadgets" (i.e., moved the address). Overhead usually 5-10% on MS Windows, about 1.5-4% on Linux (but some code actually runs faster!). The unique thing about STIR is it requires no source access and the modified binary fully works! Current work is to rewrite code to enforce security policies. For example, don't create a *.{exe,msi,bat} file. Or don't connect to the network after reading from the disk. Clowntown Express: interesting bugs and running a bug bounty program Collin Greene Collin Greene, Facebook Collin talked about Facebook's bug bounty program. Background at FB: FB has good security frameworks, such as security teams, external audits, and cc'ing on diffs. But there's lots of "deep, dark, forgotten" parts of legacy FB code. Collin gave several examples of bountied bugs. Some bounty submissions were on software purchased from a third-party (but bounty claimers don't know and don't care). We use security questions, as does everyone else, but they are basically insecure (often easily discoverable). Collin didn't expect many bugs from the bounty program, but they ended getting 20+ good bugs in first 24 hours and good submissions continue to come in. Bug bounties bring people in with different perspectives, and are paid only for success. Bug bounty is a better use of a fixed amount of time and money versus just code review or static code analysis. The Bounty program started July 2011 and paid out $1.5 million to date. 14% of the submissions have been high priority problems that needed to be fixed immediately. The best bugs come from a small % of submitters (as with everything else)—the top paid submitters are paid 6 figures a year. Spammers like to backstab competitors. The youngest sumitter was 13. Some submitters have been hired. Bug bounties also allows to see bugs that were missed by tools or reviews, allowing improvement in the process. Bug bounties might not work for traditional software companies where the product has release cycle or is not on Internet. Active Fingerprinting of Encrypted VPNs Anna Shubina Anna Shubina, Dartmouth Institute for Security, Technology, and Society (I missed the start of her talk because another track went overtime. But I have the DVD of the talk, so I'll expand later) IPsec leaves fingerprints. Using netcat, one can easily visually distinguish various crypto chaining modes just from packet timing on a chart (example, DES-CBC versus AES-CBC) One can tell a lot about VPNs just from ping roundtrips (such as what router is used) Delayed packets are not informative about a network, especially if far away from the network More needed to explore about how TCP works in real life with respect to timing Making Attacks Go Backwards Fuzzynop FuzzyNop, Mandiant This talk is not about threat attribution (finding who), product solutions, politics, or sales pitches. But who are making these malware threats? It's not a single person or group—they have diverse skill levels. There's a lot of fat-fingered fumblers out there. Always look for low-hanging fruit first: "hiding" malware in the temp, recycle, or root directories creation of unnamed scheduled tasks obvious names of files and syscalls ("ClearEventLog") uncleared event logs. Clearing event log in itself, and time of clearing, is a red flag and good first clue to look for on a suspect system Reverse engineering is hard. Disassembler use takes practice and skill. A popular tool is IDA Pro, but it takes multiple interactive iterations to get a clean disassembly. Key loggers are used a lot in targeted attacks. They are typically custom code or built in a backdoor. A big tip-off is that non-printable characters need to be printed out (such as "[Ctrl]" "[RightShift]") or time stamp printf strings. Look for these in files. Presence is not proof they are used. Absence is not proof they are not used. Java exploits. Can parse jar file with idxparser.py and decomile Java file. Java typially used to target tech companies. Backdoors are the main persistence mechanism (provided externally) for malware. Also malware typically needs command and control. Application of Artificial Intelligence in Ad-Hoc Static Code Analysis John Ashaman John Ashaman, Security Innovation Initially John tried to analyze open source files with open source static analysis tools, but these showed thousands of false positives. Also tried using grep, but tis fails to find anything even mildly complex. So next John decided to write his own tool. His approach was to first generate a call graph then analyze the graph. However, the problem is that making a call graph is really hard. For example, one problem is "evil" coding techniques, such as passing function pointer. First the tool generated an Abstract Syntax Tree (AST) with the nodes created from method declarations and edges created from method use. Then the tool generated a control flow graph with the goal to find a path through the AST (a maze) from source to sink. The algorithm is to look at adjacent nodes to see if any are "scary" (a vulnerability), using heuristics for search order. The tool, called "Scat" (Static Code Analysis Tool), currently looks for C# vulnerabilities and some simple PHP. Later, he plans to add more PHP, then JSP and Java. For more information see his posts in Security Innovation blog and NRefactory on GitHub. Mask Your Checksums—The Gorry Details Eric (XlogicX) Davisson Eric (XlogicX) Davisson Sometimes in emailing or posting TCP/IP packets to analyze problems, you may want to mask the IP address. But to do this correctly, you need to mask the checksum too, or you'll leak information about the IP. Problem reports found in stackoverflow.com, sans.org, and pastebin.org are usually not masked, but a few companies do care. If only the IP is masked, the IP may be guessed from checksum (that is, it leaks data). Other parts of packet may leak more data about the IP. TCP and IP checksums both refer to the same data, so can get more bits of information out of using both checksums than just using one checksum. Also, one can usually determine the OS from the TTL field and ports in a packet header. If we get hundreds of possible results (16x each masked nibble that is unknown), one can do other things to narrow the results, such as look at packet contents for domain or geo information. With hundreds of results, can import as CSV format into a spreadsheet. Can corelate with geo data and see where each possibility is located. Eric then demoed a real email report with a masked IP packet attached. Was able to find the exact IP address, given the geo and university of the sender. Point is if you're going to mask a packet, do it right. Eric wouldn't usually bother, but do it correctly if at all, to not create a false impression of security. Adventures with weird machines thirty years after "Reflections on Trusting Trust" Sergey Bratus Sergey Bratus, Dartmouth College (and Julian Bangert and Rebecca Shapiro, not present) "Reflections on Trusting Trust" refers to Ken Thompson's classic 1984 paper. "You can't trust code that you did not totally create yourself." There's invisible links in the chain-of-trust, such as "well-installed microcode bugs" or in the compiler, and other planted bugs. Thompson showed how a compiler can introduce and propagate bugs in unmodified source. But suppose if there's no bugs and you trust the author, can you trust the code? Hell No! There's too many factors—it's Babylonian in nature. Why not? Well, Input is not well-defined/recognized (code's assumptions about "checked" input will be violated (bug/vunerabiliy). For example, HTML is recursive, but Regex checking is not recursive. Input well-formed but so complex there's no telling what it does For example, ELF file parsing is complex and has multiple ways of parsing. Input is seen differently by different pieces of program or toolchain Any Input is a program input executes on input handlers (drives state changes & transitions) only a well-defined execution model can be trusted (regex/DFA, PDA, CFG) Input handler either is a "recognizer" for the inputs as a well-defined language (see langsec.org) or it's a "virtual machine" for inputs to drive into pwn-age ELF ABI (UNIX/Linux executible file format) case study. Problems can arise from these steps (without planting bugs): compiler linker loader ld.so/rtld relocator DWARF (debugger info) exceptions The problem is you can't really automatically analyze code (it's the "halting problem" and undecidable). Only solution is to freeze code and sign it. But you can't freeze everything! Can't freeze ASLR or loading—must have tables and metadata. Any sufficiently complex input data is the same as VM byte code Example, ELF relocation entries + dynamic symbols == a Turing Complete Machine (TM). @bxsays created a Turing machine in Linux from relocation data (not code) in an ELF file. For more information, see Rebecca "bx" Shapiro's presentation from last year's Toorcon, "Programming Weird Machines with ELF Metadata" @bxsays did same thing with Mach-O bytecode Or a DWARF exception handling data .eh_frame + glibc == Turning Machine X86 MMU (IDT, GDT, TSS): used address translation to create a Turning Machine. Page handler reads and writes (on page fault) memory. Uses a page table, which can be used as Turning Machine byte code. Example on Github using this TM that will fly a glider across the screen Next Sergey talked about "Parser Differentials". That having one input format, but two parsers, will create confusion and opportunity for exploitation. For example, CSRs are parsed during creation by cert requestor and again by another parser at the CA. Another example is ELF—several parsers in OS tool chain, which are all different. Can have two different Program Headers (PHDRs) because ld.so parses multiple PHDRs. The second PHDR can completely transform the executable. This is described in paper in the first issue of International Journal of PoC. Conclusions trusting computers not only about bugs! Bugs are part of a problem, but no by far all of it complex data formats means bugs no "chain of trust" in Babylon! (that is, with parser differentials) we need to squeeze complexity out of data until data stops being "code equivalent" Further information See and langsec.org. USENIX WOOT 2013 (Workshop on Offensive Technologies) for "weird machines" papers and videos.

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  • No sound after video card replaced (AMD Radeon HD 7770)

    - by Sean
    Issue: no sound System: Dual boot Windows 7 (sda) Ubuntu 12.04 (sdb) 2 harddrives Dell XPS 730 Video card: AMD Radeo HD 7770 Diamond Multimedia Sound card: Creative Labs SB X-Fi Additional info: My sound used to work. Then, my old video card (NVIDIA geforce 280) died. I bought and installed a new video card: Radeon HD 7770. After this, my sound no longer worked in ubuntu (Win7 audio still works). Everything else in ubuntu, such as video, works fine. I suspect it has something to do with the fact that the Radeon card includes sound capability. Problem Details: If I click on System Settings - Sound, the panel freezes and stops responding indefinitely. The sound volume icon at the top of the screen (by the clock) shows 3 dashes beside it "---", and an empty drop-down box shows if I click on it. (Possibly related to 1.) When I reboot my machine, I get the message: "gnome settings daemon not responding". I have to force the reboot. I reinstalled ubunbu (perserving my home directory) and the problem persists. Diagnostics info: Following procedure outlined here: https://help.ubuntu.com/community/SoundTroubleshooting The following is a list of terminal commands, and their output: $ aplay -l List of PLAYBACK Hardware Devices There is no listing beyond that, and the command freezes until I hit control-c $ lspci -v | grep -A7 -i "audio" 00:0f.1 Audio device: NVIDIA Corporation MCP55 High Definition Audio (rev a2) Subsystem: Dell Device 0224 Flags: bus master, 66MHz, fast devsel, latency 0, IRQ 23 Memory at dfff0000 (32-bit, non-prefetchable) [size=16K] Capabilities: <access denied> Kernel driver in use: snd_hda_intel Kernel modules: snd-hda-intel -- 01:00.1 Audio device: Advanced Micro Devices [AMD] nee ATI Device aab0 Subsystem: Diamond Multimedia Systems Device aab0 Flags: bus master, fast devsel, latency 0, IRQ 43 Memory at dfefc000 (64-bit, non-prefetchable) [size=16K] Capabilities: <access denied> Kernel driver in use: snd_hda_intel Kernel modules: snd-hda-intel -- 03:0a.0 Audio device: Creative Labs SB X-Fi Subsystem: Creative Labs Device 6002 Flags: bus master, medium devsel, latency 32, IRQ 18 Memory at dbff4000 (32-bit, non-prefetchable) [size=16K] Memory at dbc00000 (64-bit, non-prefetchable) [size=2M] Memory at d4000000 (64-bit, non-prefetchable) [size=64M] I/O ports at 8c00 [size=32] Capabilities: <access denied> Notice the Diamond Multimedia Systems Device - that seems to be my video card sound. My video card is Diamond multimedia. Also there's the weird NVIDIA device in there. That must either be a remnant of my now removed NVIDIA graphics card, or else some kind of on-board thing. Not sure which. $ killall pulseaudio This allows me to open system settings - sound. But the "Test Sound" button makes no sound And the output volume + mute controls are greyed / disabled at 0 volume. It also allows me to click on the sound control in the "task bar" (beside the clock), and a volume slider drops down, but it is disabled / greyed at 0 volume. $ find /lib/modules/uname -r | grep snd /lib/modules/3.2.0-29-generic-pae/kernel/sound/soc/codecs/snd-soc-88pm860x.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/soc/codecs/snd-soc-tlv320aic3x.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/soc/codecs/snd-soc-wm8900.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/soc/codecs/snd-soc-wm8978.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/soc/codecs/snd-soc-tlv320dac33.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/soc/codecs/snd-soc-wm9090.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/soc/codecs/snd-soc-sta32x.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/soc/codecs/snd-soc-max98088.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/soc/codecs/snd-soc-max9850.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/soc/codecs/snd-soc-rt5631.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/soc/codecs/snd-soc-wm8903.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/soc/codecs/snd-soc-wm8580.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/soc/codecs/snd-soc-wm8523.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/soc/codecs/snd-soc-max9877.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/soc/codecs/snd-soc-ads117x.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/soc/codecs/snd-soc-wm8955.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/soc/codecs/snd-soc-wm8804.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/soc/codecs/snd-soc-sgtl5000.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/soc/codecs/snd-soc-wm8750.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/soc/codecs/snd-soc-wm2000.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/soc/codecs/snd-soc-tlv320aic32x4.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/soc/codecs/snd-soc-ak4642.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/soc/codecs/snd-soc-ad193x.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/soc/codecs/snd-soc-wm8753.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/soc/codecs/snd-soc-ak4535.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/soc/codecs/snd-soc-wm8985.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/soc/codecs/snd-soc-wm8350.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/soc/codecs/snd-soc-dfbmcs320.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/soc/codecs/snd-soc-cs42l51.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/soc/codecs/snd-soc-tlv320aic26.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/soc/codecs/snd-soc-wm8737.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/soc/codecs/snd-soc-uda1380.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/soc/codecs/snd-soc-wm8776.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/soc/codecs/snd-soc-wm8995.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/soc/codecs/snd-soc-tpa6130a2.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/soc/codecs/snd-soc-wm8727.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/soc/codecs/snd-soc-wm5100.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/soc/codecs/snd-soc-wm8991.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/soc/codecs/snd-soc-wm8510.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/soc/codecs/snd-soc-jz4740-codec.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/soc/codecs/snd-soc-wm8400.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/soc/codecs/snd-soc-lm4857.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/soc/codecs/snd-soc-wm8960.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/soc/codecs/snd-soc-alc5623.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/soc/codecs/snd-soc-cs4270.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/soc/codecs/snd-soc-tlv320aic23.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/soc/codecs/snd-soc-wm8993.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/soc/codecs/snd-soc-wm8961.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/soc/codecs/snd-soc-wm8940.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/soc/codecs/snd-soc-uda134x.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/soc/codecs/snd-soc-ad1836.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/soc/codecs/snd-soc-wm8994.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/soc/codecs/snd-soc-wm8782.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/soc/codecs/snd-soc-cs4271.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/soc/codecs/snd-soc-wm8974.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/soc/codecs/snd-soc-wm8983.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/soc/codecs/snd-soc-wm8962.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/soc/codecs/snd-soc-ak4641.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/soc/codecs/snd-soc-wm-hubs.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/soc/codecs/snd-soc-wm8971.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/soc/codecs/snd-soc-wm8996.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/soc/codecs/snd-soc-wl1273.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/soc/codecs/snd-soc-adav80x.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/soc/codecs/snd-soc-spdif.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/soc/codecs/snd-soc-pcm3008.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/soc/codecs/snd-soc-cx20442.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/soc/codecs/snd-soc-ak4671.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/soc/codecs/snd-soc-wm8711.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/soc/codecs/snd-soc-ad73311.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/soc/codecs/snd-soc-max98095.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/soc/codecs/snd-soc-wm9081.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/soc/codecs/snd-soc-wm8741.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/soc/codecs/snd-soc-wm1250-ev1.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/soc/codecs/snd-soc-wm8988.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/soc/codecs/snd-soc-adau1373.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/soc/codecs/snd-soc-wm8731.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/soc/codecs/snd-soc-l3.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/soc/codecs/snd-soc-ssm2602.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/soc/codecs/snd-soc-da7210.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/soc/codecs/snd-soc-ak4104.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/soc/codecs/snd-soc-wm8904.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/soc/codecs/snd-soc-wm8728.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/soc/codecs/snd-soc-wm8770.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/soc/codecs/snd-soc-wm8990.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/soc/snd-soc-core.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/synth/emux/snd-emux-synth.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/synth/snd-util-mem.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/core/snd-hrtimer.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/core/snd-hwdep.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/core/snd-pcm.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/core/snd-rawmidi.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/core/oss/snd-mixer-oss.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/core/snd-page-alloc.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/core/seq/snd-seq-midi.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/core/seq/snd-seq-dummy.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/core/seq/snd-seq-virmidi.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/core/seq/snd-seq-device.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/core/seq/snd-seq-midi-event.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/core/seq/snd-seq.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/core/seq/snd-seq-midi-emul.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/core/snd.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/core/snd-timer.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/pcmcia/pdaudiocf/snd-pdaudiocf.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/pcmcia/vx/snd-vxpocket.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/usb/6fire/snd-usb-6fire.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/usb/snd-usbmidi-lib.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/usb/caiaq/snd-usb-caiaq.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/usb/usx2y/snd-usb-usx2y.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/usb/usx2y/snd-usb-us122l.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/usb/snd-usb-audio.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/usb/misc/snd-ua101.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/drivers/opl3/snd-opl3-synth.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/drivers/opl3/snd-opl3-lib.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/drivers/opl4/snd-opl4-lib.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/drivers/opl4/snd-opl4-synth.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/drivers/snd-portman2x4.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/drivers/snd-serial-u16550.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/drivers/snd-mts64.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/drivers/snd-mtpav.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/drivers/mpu401/snd-mpu401.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/drivers/mpu401/snd-mpu401-uart.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/drivers/vx/snd-vx-lib.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/drivers/snd-dummy.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/drivers/snd-aloop.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/drivers/pcsp/snd-pcsp.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/drivers/snd-virmidi.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/firewire/snd-firewire-lib.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/firewire/snd-firewire-speakers.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/firewire/snd-isight.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/i2c/snd-tea6330t.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/i2c/other/snd-tea575x-tuner.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/i2c/other/snd-ak4113.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/i2c/other/snd-pt2258.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/i2c/other/snd-ak4117.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/i2c/other/snd-ak4xxx-adda.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/i2c/other/snd-ak4114.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/i2c/snd-cs8427.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/i2c/snd-i2c.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/pci/emu10k1/snd-emu10k1-synth.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/pci/emu10k1/snd-emu10k1.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/pci/emu10k1/snd-emu10k1x.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/pci/korg1212/snd-korg1212.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/pci/au88x0/snd-au8830.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/pci/au88x0/snd-au8820.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/pci/au88x0/snd-au8810.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/pci/aw2/snd-aw2.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/pci/snd-sis7019.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/pci/snd-ens1371.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/pci/vx222/snd-vx222.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/pci/snd-via82xx.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/pci/snd-es1968.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/pci/snd-atiixp-modem.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/pci/snd-cs4281.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/pci/snd-sonicvibes.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/pci/snd-intel8x0.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/pci/snd-maestro3.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/pci/ac97/snd-ac97-codec.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/pci/snd-es1938.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/pci/snd-fm801.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/pci/nm256/snd-nm256.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/pci/hda/snd-hda-codec-realtek.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/pci/hda/snd-hda-codec-cmedia.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/pci/hda/snd-hda-codec-conexant.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/pci/hda/snd-hda-intel.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/pci/hda/snd-hda-codec-analog.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/pci/hda/snd-hda-codec-hdmi.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/pci/hda/snd-hda-codec-idt.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/pci/hda/snd-hda-codec-ca0110.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/pci/hda/snd-hda-codec-cirrus.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/pci/hda/snd-hda-codec-via.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/pci/hda/snd-hda-codec-ca0132.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/pci/hda/snd-hda-codec-si3054.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/pci/hda/snd-hda-codec.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/pci/riptide/snd-riptide.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/pci/snd-ens1370.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/pci/snd-als4000.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/pci/snd-intel8x0m.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/pci/ca0106/snd-ca0106.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/pci/snd-cs5530.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/pci/cs5535audio/snd-cs5535audio.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/pci/snd-rme32.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/pci/ymfpci/snd-ymfpci.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/pci/ctxfi/snd-ctxfi.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/pci/snd-azt3328.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/pci/cs46xx/snd-cs46xx.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/pci/lx6464es/snd-lx6464es.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/pci/ice1712/snd-ice1712.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/pci/ice1712/snd-ice17xx-ak4xxx.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/pci/ice1712/snd-ice1724.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/pci/mixart/snd-mixart.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/pci/ali5451/snd-ali5451.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/pci/lola/snd-lola.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/pci/oxygen/snd-oxygen-lib.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/pci/oxygen/snd-oxygen.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/pci/oxygen/snd-virtuoso.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/pci/snd-via82xx-modem.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/pci/pcxhr/snd-pcxhr.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/pci/echoaudio/snd-indigo.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/pci/echoaudio/snd-echo3g.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/pci/echoaudio/snd-mona.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/pci/echoaudio/snd-layla20.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/pci/echoaudio/snd-gina20.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/pci/echoaudio/snd-layla24.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/pci/echoaudio/snd-mia.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/pci/echoaudio/snd-indigoiox.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/pci/echoaudio/snd-darla24.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/pci/echoaudio/snd-indigoio.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/pci/echoaudio/snd-indigodjx.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/pci/echoaudio/snd-gina24.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/pci/echoaudio/snd-darla20.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/pci/echoaudio/snd-indigodj.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/pci/snd-cmipci.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/pci/asihpi/snd-asihpi.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/pci/snd-ad1889.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/pci/rme9652/snd-rme9652.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/pci/rme9652/snd-hdspm.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/pci/rme9652/snd-hdsp.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/pci/trident/snd-trident.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/pci/snd-atiixp.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/pci/snd-als300.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/pci/snd-bt87x.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/pci/snd-rme96.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/isa/opti9xx/snd-miro.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/isa/opti9xx/snd-opti92x-ad1848.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/isa/opti9xx/snd-opti93x.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/isa/opti9xx/snd-opti92x-cs4231.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/isa/gus/snd-gusextreme.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/isa/gus/snd-interwave.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/isa/gus/snd-gusmax.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/isa/gus/snd-interwave-stb.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/isa/gus/snd-gus-lib.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/isa/gus/snd-gusclassic.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/isa/sb/snd-emu8000-synth.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/isa/sb/snd-sb16-dsp.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/isa/sb/snd-sbawe.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/isa/sb/snd-sb8-dsp.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/isa/sb/snd-sb-common.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/isa/sb/snd-sb16.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/isa/sb/snd-sb16-csp.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/isa/sb/snd-sb8.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/isa/sb/snd-jazz16.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/isa/snd-es18xx.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/isa/snd-azt2320.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/isa/snd-cmi8330.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/isa/snd-als100.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/isa/msnd /lib/modules/3.2.0-29-generic-pae/kernel/sound/isa/msnd/snd-msnd-classic.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/isa/msnd/snd-msnd-pinnacle.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/isa/msnd/snd-msnd-lib.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/isa/cs423x/snd-cs4231.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/isa/cs423x/snd-cs4236.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/isa/es1688/snd-es1688-lib.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/isa/es1688/snd-es1688.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/isa/snd-adlib.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/isa/ad1848/snd-ad1848.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/isa/ad1816a/snd-ad1816a.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/isa/galaxy/snd-azt1605.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/isa/galaxy/snd-azt2316.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/isa/wavefront/snd-wavefront.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/isa/wss/snd-wss-lib.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/isa/snd-sc6000.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/isa/snd-sscape.ko /lib/modules/3.2.0-29-generic-pae/kernel/sound/isa/snd-opl3sa2.ko

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  • Know more about Enqueue Deadlock Detection

    - by Liu Maclean(???)
    ??? ORACLE ALLSTAR???????????????????,??????? ???????enqueue lock?????????3 ??????,????????????????????????????ora-00060 dead lock??process???3s: SQL> select * from v$version; BANNER ---------------------------------------------------------------- Oracle Database 10g Enterprise Edition Release 10.2.0.5.0 - 64bi PL/SQL Release 10.2.0.5.0 - Production CORE 10.2.0.5.0 Production TNS for Linux: Version 10.2.0.5.0 - Production NLSRTL Version 10.2.0.5.0 - Production SQL> select * from global_name; GLOBAL_NAME -------------------------------------------------------------------------------- www.oracledatabase12g.com PROCESS A: set timing on; update maclean1 set t1=t1+1; PROCESS B: update maclean2 set t1=t1+1; PROCESS A: update maclean2 set t1=t1+1; PROCESS B: update maclean1 set t1=t1+1; ??3s? PROCESS A ?? ERROR at line 1: ORA-00060: deadlock detected while waiting for resource Elapsed: 00:00:03.02 ????Process A????????????? 3s,?????????????,??????? ?????????? ???????: SQL> col name for a30 SQL> col value for a5 SQL> col DESCRIB for a50 SQL> set linesize 140 pagesize 1400 SQL> SELECT x.ksppinm NAME, y.ksppstvl VALUE, x.ksppdesc describ 2 FROM SYS.x$ksppi x, SYS.x$ksppcv y 3 WHERE x.inst_id = USERENV ('Instance') 4 AND y.inst_id = USERENV ('Instance') 5 AND x.indx = y.indx 6 AND x.ksppinm='_enqueue_deadlock_scan_secs'; NAME VALUE DESCRIB ------------------------------ ----- -------------------------------------------------- _enqueue_deadlock_scan_secs 0 deadlock scan interval SQL> alter system set "_enqueue_deadlock_scan_secs"=18 scope=spfile; System altered. Elapsed: 00:00:00.01 SQL> startup force; ORACLE instance started. Total System Global Area 851443712 bytes Fixed Size 2100040 bytes Variable Size 738198712 bytes Database Buffers 104857600 bytes Redo Buffers 6287360 bytes Database mounted. Database opened. PROCESS A: SQL> set timing on; SQL> update maclean1 set t1=t1+1; 1 row updated. Elapsed: 00:00:00.06 Process B SQL> update maclean2 set t1=t1+1; 1 row updated. SQL> update maclean1 set t1=t1+1; Process A: SQL> SQL> alter session set events '10704 trace name context forever,level 10:10046 trace name context forever,level 8'; Session altered. SQL> update maclean2 set t1=t1+1; update maclean2 set t1=t1+1 * ERROR at line 1: ORA-00060: deadlock detected while waiting for resource  Elapsed: 00:00:18.05 ksqcmi: TX,90011,4a9 mode=6 timeout=21474836 WAIT #12: nam='enq: TX - row lock contention' ela= 2930070 name|mode=1415053318 usn<<16 | slot=589841 sequence=1193 obj#=56810 tim=1308114759849120 WAIT #12: nam='enq: TX - row lock contention' ela= 2930636 name|mode=1415053318 usn<<16 | slot=589841 sequence=1193 obj#=56810 tim=1308114762779801 WAIT #12: nam='enq: TX - row lock contention' ela= 2930439 name|mode=1415053318 usn<<16 | slot=589841 sequence=1193 obj#=56810 tim=1308114765710430 *** 2012-06-12 09:58:43.089 WAIT #12: nam='enq: TX - row lock contention' ela= 2931698 name|mode=1415053318 usn<<16 | slot=589841 sequence=1193 obj#=56810 tim=1308114768642192 WAIT #12: nam='enq: TX - row lock contention' ela= 2930428 name|mode=1415053318 usn<<16 | slot=589841 sequence=1193 obj#=56810 tim=1308114771572755 WAIT #12: nam='enq: TX - row lock contention' ela= 2931408 name|mode=1415053318 usn<<16 | slot=589841 sequence=1193 obj#=56810 tim=1308114774504207 DEADLOCK DETECTED ( ORA-00060 ) [Transaction Deadlock] The following deadlock is not an ORACLE error. It is a deadlock due to user error in the design of an application or from issuing incorrect ad-hoc SQL. The following information may aid in determining the deadlock: ??????Process A?’enq: TX – row lock contention’ ?????ORA-00060 deadlock detected????3s ??? 18s , ???hidden parameter “_enqueue_deadlock_scan_secs”?????,????????0? ??????????: SQL> alter system set "_enqueue_deadlock_scan_secs"=4 scope=spfile; System altered. Elapsed: 00:00:00.01 SQL> alter system set "_enqueue_deadlock_time_sec"=9 scope=spfile; System altered. Elapsed: 00:00:00.00 SQL> startup force; ORACLE instance started. Total System Global Area 851443712 bytes Fixed Size 2100040 bytes Variable Size 738198712 bytes Database Buffers 104857600 bytes Redo Buffers 6287360 bytes Database mounted. Database opened. SQL> set linesize 140 pagesize 1400 SQL> show parameter dead NAME TYPE VALUE ------------------------------------ -------------------------------- ------------------------------ _enqueue_deadlock_scan_secs integer 4 _enqueue_deadlock_time_sec integer 9 SQL> set timing on SQL> select * from maclean1 for update wait 8; T1 ---------- 11 Elapsed: 00:00:00.01 PROCESS B SQL> select * from maclean2 for update wait 8; T1 ---------- 3 SQL> select * from maclean1 for update wait 8; select * from maclean1 for update wait 8 PROCESS A SQL> select * from maclean2 for update wait 8; select * from maclean2 for update wait 8 * ERROR at line 1: ORA-30006: resource busy; acquire with WAIT timeout expired Elapsed: 00:00:08.00 ???????? ??? select for update wait?enqueue request timeout ?????8s? ,???????”_enqueue_deadlock_scan_secs”=4(deadlock scan interval),?4s???deadlock detected,????Process A????deadlock ???, ??????? ??Process A?????8s?raised??”ORA-30006: resource busy; acquire with WAIT timeout expired”??,??ORA-00060,?????process A???????? ????????”_enqueue_deadlock_time_sec”(requests with timeout <= this will not have deadlock detection)???,?enqueue request time < “_enqueue_deadlock_time_sec”?Server process?????dead lock detection,?????????enqueue request ??????timeout??????(_enqueue_deadlock_time_sec????5,?timeout<5s),???????????????;??????timeout>”_enqueue_deadlock_time_sec”???,Oracle????????????????????? ??????????: SQL> show parameter dead NAME TYPE VALUE ------------------------------------ -------------------------------- ------------------------------ _enqueue_deadlock_scan_secs integer 4 _enqueue_deadlock_time_sec integer 9 Process A: SQL> set timing on; SQL> select * from maclean1 for update wait 10; T1 ---------- 11 Process B: SQL> select * from maclean2 for update wait 10; T1 ---------- 3 SQL> select * from maclean1 for update wait 10; PROCESS A: SQL> select * from maclean2 for update wait 10; select * from maclean2 for update wait 10 * ERROR at line 1: ORA-00060: deadlock detected while waiting for resource Elapsed: 00:00:06.02 ??????? select for update wait 10?10s??, ?? 10s?????_enqueue_deadlock_time_sec???(9s),??Process A???????? ???????????????6s ???????_enqueue_deadlock_scan_secs?4s ? ???????????,???????????_enqueue_deadlock_scan_secs?????????3???? ??: enqueue lock?????????????? 1. ?????????deadlock detection??3s????, ????????_enqueue_deadlock_scan_secs(deadlock scan interval)???,??????0,????????_enqueue_deadlock_scan_secs?????????3???, ?_enqueue_deadlock_scan_secs=0 ??3s??, ?_enqueue_deadlock_scan_secs=4??6s??,????? 2. ???????_enqueue_deadlock_time_sec(requests with timeout <= this will not have deadlock detection)???,?enqueue request timeout< _enqueue_deadlock_time_sec(????5),?Server process?????????enqueue request timeout>_enqueue_deadlock_time_sec ????_enqueue_deadlock_scan_secs???????, ??request timeout??????select for update wait [TIMEOUT]??? ??: ???10.2.0.1?????????2?hidden parameter , ???patchset 10.2.0.3????? _enqueue_deadlock_time_sec, ?patchset 10.2.0.5??????_enqueue_deadlock_scan_secs? ?????RAC???????????10s, ???????_lm_dd_interval(dd time interval in seconds) ,????????8.0.6???? ???????????????,??????,  ?10g???????60s,?11g???????10s?  ???????11g??_lm_dd_interval?????????????,?????11g??LMD????????????,??????????RAC?LMD?Deadlock Detection???????CPU,???11g?Oracle????Team???LMD????????CPU????: ????????11g?LMD???????,???????11g??? UTS TRACE ????? DD???: SQL> select * from v$version; BANNER -------------------------------------------------------------------------------- Oracle Database 11g Enterprise Edition Release 11.2.0.3.0 - 64bit Production PL/SQL Release 11.2.0.3.0 - Production CORE 11.2.0.3.0 Production TNS for Linux: Version 11.2.0.3.0 - Production NLSRTL Version 11.2.0.3.0 - Production SQL> SQL> select * from global_name 2 ; GLOBAL_NAME -------------------------------------------------------------------------------- www.oracledatabase12g.com SQL> alter system set "_lm_dd_interval"=20 scope=spfile; System altered. SQL> startup force; ORACLE instance started. Total System Global Area 1570009088 bytes Fixed Size 2228704 bytes Variable Size 1325403680 bytes Database Buffers 234881024 bytes Redo Buffers 7495680 bytes Database mounted. Database opened. SQL> set linesize 140 pagesize 1400 SQL> show parameter lm_dd NAME TYPE VALUE ------------------------------------ -------------------------------- ------------------------------ _lm_dd_interval integer 20 SQL> select count(*) from gv$instance; COUNT(*) ---------- 2 instance 1: SQL> oradebug setorapid 12 Oracle pid: 12, Unix process pid: 8608, image: [email protected] (LMD0) ? LMD0??? UTS TRACE??RAC???????????? SQL> oradebug event 10046 trace name context forever,level 8:10708 trace name context forever,level 103: trace[rac.*] disk high; Statement processed. Elapsed: 00:00:00.00 SQL> update maclean1 set t1=t1+1; 1 row updated. instance 2: SQL> update maclean2 set t1=t1+1; 1 row updated. SQL> update maclean1 set t1=t1+1; Instance 1: SQL> update maclean2 set t1=t1+1; update maclean2 set t1=t1+1 * ERROR at line 1: ORA-00060: deadlock detected while waiting for resource Elapsed: 00:00:20.51 LMD0???UTS TRACE 2012-06-12 22:27:00.929284 : [kjmpbmsg:process][type 22][msg 0x7fa620ac85a8][from 1][seq 8148.0][len 192] 2012-06-12 22:27:00.929346 : [kjmxmpm][type 22][seq 0.0][msg 0x7fa620ac85a8][from 1] *** 2012-06-12 22:27:00.929 * kjddind: received DDIND msg with subtype x6 * reqp->dd_master_inst_kjxmddi == 1 * kjddind: dump sgh: 2012-06-12 22:27:00.929346*: kjddind: req->timestamp [0.15], kjddt [0.13] 2012-06-12 22:27:00.929346*: >> DDmsg:KJX_DD_REMOTE,TS[0.15],Inst 1->2,ddxid[id1,id2,inst:2097153,31,1],ddlock[0x95023930,829],ddMasterInst 1 2012-06-12 22:27:00.929346*: lock [0x95023930,829], op = [mast] 2012-06-12 22:27:00.929346*: reqp->timestamp [0.15], kjddt [0.13] 2012-06-12 22:27:00.929346*: kjddind: updated local timestamp [0.15] * kjddind: case KJX_DD_REMOTE 2012-06-12 22:27:00.929346*: ADD IO NODE WFG: 0 frame pointer 2012-06-12 22:27:00.929346*: PUSH: type=res, enqueue(0xffffffff.0xffffffff)=0xbbb9af40, block=KJUSEREX, snode=1 2012-06-12 22:27:00.929346*: PROCESS: type=res, enqueue(0xffffffff.0xffffffff)=0xbbb9af40, block=KJUSEREX, snode=1 2012-06-12 22:27:00.929346*: POP: type=res, enqueue(0xffffffff.0xffffffff)=0xbbb9af40, block=KJUSEREX, snode=1 2012-06-12 22:27:00.929346*: kjddopr[TX 0xe000c.0x32][ext 0x5,0x0]: blocking lock 0xbbb9a800, owner 2097154 of inst 2 2012-06-12 22:27:00.929346*: PUSH: type=txn, enqueue(0xffffffff.0xffffffff)=0xbbb9a800, block=KJUSEREX, snode=1 2012-06-12 22:27:00.929346*: PROCESS: type=txn, enqueue(0xffffffff.0xffffffff)=0xbbb9a800, block=KJUSEREX, snode=1 2012-06-12 22:27:00.929346*: ADD NODE TO WFG: type=txn, enqueue(0xffffffff.0xffffffff)=0xbbb9a800, block=KJUSEREX, snode=1 2012-06-12 22:27:00.929346*: POP: type=txn, enqueue(0xffffffff.0xffffffff)=0xbbb9a800, block=KJUSEREX, snode=1 2012-06-12 22:27:00.929346*: kjddopt: converting lock 0xbbce92f8 on 'TX' 0x80016.0x5d4,txid [2097154,34]of inst 2 2012-06-12 22:27:00.929346*: PUSH: type=res, enqueue(0xffffffff.0xffffffff)=0xbbce92f8, block=KJUSEREX, snode=1 2012-06-12 22:27:00.929346*: PROCESS: type=res, enqueue(0xffffffff.0xffffffff)=0xbbce92f8, block=KJUSEREX, snode=1 2012-06-12 22:27:00.929346*: ADD NODE TO WFG: type=res, enqueue(0xffffffff.0xffffffff)=0xbbce92f8, block=KJUSEREX, snode=1 2012-06-12 22:27:00.929855 : GSIPC:AMBUF: rcv buff 0x7fa620aa8cd8, pool rcvbuf, rqlen 1102 2012-06-12 22:27:00.929878 : GSIPC:GPBMSG: new bmsg 0x7fa620aa8d48 mb 0x7fa620aa8cd8 msg 0x7fa620aa8d68 mlen 192 dest x100 flushsz -1 2012-06-12 22:27:00.929878*: << DDmsg:KJX_DD_REMOTE,TS[0.15],Inst 2->1,ddxid[id1,id2,inst:2097153,31,1],ddlock[0x95023930,829],ddMasterInst 1 2012-06-12 22:27:00.929878*: lock [0xbbce92f8,287], op = [mast] 2012-06-12 22:27:00.929878*: ADD IO NODE WFG: 0 frame pointer 2012-06-12 22:27:00.929923 : [kjmpbmsg:compl][msg 0x7fa620ac8588][typ p][nmsgs 1][qtime 0][ptime 0] 2012-06-12 22:27:00.929947 : GSIPC:PBAT: flush start. flag 0x79 end 0 inc 4.4 2012-06-12 22:27:00.929963 : GSIPC:PBAT: send bmsg 0x7fa620aa8d48 blen 224 dest 1.0 2012-06-12 22:27:00.929979 : GSIPC:SNDQ: enq msg 0x7fa620aa8d48, type 65521 seq 8325, inst 1, receiver 0, queued 1 012-06-12 22:27:00.929979 : GSIPC:SNDQ: enq msg 0x7fa620aa8d48, type 65521 seq 8325, inst 1, receiver 0, queued 1 2012-06-12 22:27:00.929996 : GSIPC:BSEND: flushing sndq 0xb491dd28, id 0, dcx 0xbc517770, inst 1, rcvr 0 qlen 0 1 2012-06-12 22:27:00.930014 : GSIPC:BSEND: no batch1 msg 0x7fa620aa8d48 type 65521 len 224 dest (1:0) 2012-06-12 22:27:00.930088 : kjbsentscn[0x0.3f72dc][to 1] 2012-06-12 22:27:00.930144 : GSIPC:SENDM: send msg 0x7fa620aa8d48 dest x10000 seq 8325 type 65521 tkts x1 mlen xe00110 2012-06-12 22:27:00.930531 : GSIPC:KSXPCB: msg 0x7fa620aa8d48 status 30, type 65521, dest 1, rcvr 0 WAIT #0: nam='ges remote message' ela= 1372 waittime=80 loop=0 p3=74 obj#=-1 tim=1339554420931640 2012-06-12 22:27:00.931728 : GSIPC:RCVD: ksxp msg 0x7fa620af6490 sndr 1 seq 0.8149 type 65521 tkts 1 2012-06-12 22:27:00.931746 : GSIPC:RCVD: watq msg 0x7fa620af6490 sndr 1, seq 8149, type 65521, tkts 1 2012-06-12 22:27:00.931763 : GSIPC:RCVD: seq update (0.8148)->(0.8149) tp -15 fg 0x4 from 1 pbattr 0x0 2012-06-12 22:27:00.931779 : GSIPC:TKT: collect msg 0x7fa620af6490 from 1 for rcvr 0, tickets 1 2012-06-12 22:27:00.931794 : kjbrcvdscn[0x0.3f72dc][from 1][idx 2012-06-12 22:27:00.931810 : kjbrcvdscn[no bscn dd_master_inst_kjxmddi == 1 * kjddind: dump sgh: NXTIN (nil) 0 wq 0 cvtops x0 0x0.0x0(ext 0x0,0x0)[0000-0000-00000000] inst 1 BLOCKER 0xbbb9a800 5 wq 1 cvtops x28 TX 0xe000c.0x32(ext 0x5,0x0)[20000-0002-00000022] inst 2 BLOCKED 0xbbce92f8 5 wq 2 cvtops x1 TX 0x80016.0x5d4(ext 0x2,0x0)[20000-0002-00000022] inst 2 NXTOUT (nil) 0 wq 0 cvtops x0 0x0.0x0(ext 0x0,0x0)[0000-0000-00000000] inst 1 2012-06-12 22:27:00.932058*: kjddind: req->timestamp [0.15], kjddt [0.15] 2012-06-12 22:27:00.932058*: >> DDmsg:KJX_DD_VALIDATE,TS[0.15],Inst 1->2,ddxid[id1,id2,inst:2097153,31,1],ddlock[0x95023930,829],ddMasterInst 1 2012-06-12 22:27:00.932058*: lock [(nil),0], op = [vald_dd] 2012-06-12 22:27:00.932058*: kjddind: updated local timestamp [0.15] * kjddind: case KJX_DD_VALIDATE *** 2012-06-12 22:27:00.932 * kjddvald called: kjxmddi stuff: * cont_lockp (nil) * dd_lockp 0x95023930 * dd_inst 1 * dd_master_inst 1 * sgh graph: NXTIN (nil) 0 wq 0 cvtops x0 0x0.0x0(ext 0x0,0x0)[0000-0000-00000000] inst 1 BLOCKER 0xbbb9a800 5 wq 1 cvtops x28 TX 0xe000c.0x32(ext 0x5,0x0)[20000-0002-00000022] inst 2 BLOCKED 0xbbce92f8 5 wq 2 cvtops x1 TX 0x80016.0x5d4(ext 0x2,0x0)[20000-0002-00000022] inst 2 NXTOUT (nil) 0 wq 0 cvtops x0 0x0.0x0(ext 0x0,0x0)[0000-0000-00000000] inst 1 POP WFG NODE: lock=(nil) * kjddvald: dump the PRQ: BLOCKER 0xbbb9a800 5 wq 1 cvtops x28 TX 0xe000c.0x32(ext 0x5,0x0)[20000-0002-00000022] inst 2 BLOCKED 0xbbce92f8 5 wq 2 cvtops x1 TX 0x80016.0x5d4(ext 0x2,0x0)[20000-0002-00000022] inst 2 * kjddvald: KJDD_NXTONOD ->node_kjddsg.dinst_kjddnd =1 * kjddvald: ... which is not my node, my subgraph is validated but the cycle is not complete Global blockers dump start:--------------------------------- DUMP LOCAL BLOCKER/HOLDER: block level 5 res [0x80016][0x5d4],[TX][ext 0x2,0x0] ??dead lock!!! ???????11.2.0.3???? RAC LMD???????????”_lm_dd_interval”????????????20s?  ???????10g?_lm_dd_interval???60s,??????Processes?????????????????,????????????Server Process????????60s??????11g?????(??????LMD???????)???????,???????????10s??? Enqueue Deadlock Detection? ?11g??? RAC?LMD???????hidden parameter ????”_lm_dd_interval”???,RAC????????????????,???????????: SQL> col name for a50 SQL> col describ for a60 SQL> col value for a20 SQL> set linesize 140 pagesize 1400 SQL> SELECT x.ksppinm NAME, y.ksppstvl VALUE, x.ksppdesc describ 2 FROM SYS.x$ksppi x, SYS.x$ksppcv y 3 WHERE x.inst_id = USERENV ('Instance') 4 AND y.inst_id = USERENV ('Instance') 5 AND x.indx = y.indx 6 AND x.ksppinm like '_lm_dd%'; NAME VALUE DESCRIB -------------------------------------------------- -------------------- ------------------------------------------------------------ _lm_dd_interval 20 dd time interval in seconds _lm_dd_scan_interval 5 dd scan interval in seconds _lm_dd_search_cnt 3 number of dd search per token get _lm_dd_max_search_time 180 max dd search time per token _lm_dd_maxdump 50 max number of locks to be dumped during dd validation _lm_dd_ignore_nodd FALSE if TRUE nodeadlockwait/nodeadlockblock options are ignored 6 rows selected.

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  • Windows Phone 7: Building a simple dictionary web client

    - by TechTwaddle
    Like I mentioned in this post a while back, I came across a dictionary web service called Aonaware that serves up word definitions from various dictionaries and is really easy to use. The services page on their website, http://services.aonaware.com/DictService/DictService.asmx, lists all the operations that are supported by the dictionary service. Here they are, Word Dictionary Web Service The following operations are supported. For a formal definition, please review the Service Description. Define Define given word, returning definitions from all dictionaries DefineInDict Define given word, returning definitions from specified dictionary DictionaryInfo Show information about the specified dictionary DictionaryList Returns a list of available dictionaries DictionaryListExtended Returns a list of advanced dictionaries (e.g. translating dictionaries) Match Look for matching words in all dictionaries using the given strategy MatchInDict Look for matching words in the specified dictionary using the given strategy ServerInfo Show remote server information StrategyList Return list of all available strategies on the server Follow the links above to get more information on each API. In this post we will be building a simple windows phone 7 client which uses this service to get word definitions for words entered by the user. The application will also allow the user to select a dictionary from all the available ones and look up the word definition in that dictionary. So of all the apis above we will be using only two, DictionaryList() to get a list of all supported dictionaries and DefineInDict() to get the word definition from a particular dictionary. Before we get started, a note to you all; I would have liked to implement this application using concepts from data binding, item templates, data templates etc. I have a basic understanding of what they are but, being a beginner, I am not very comfortable with those topics yet so I didn’t use them. I thought I’ll get this version out of the way and maybe in the next version I could give those a try. A somewhat scary mock-up of the what the final application will look like, Select Dictionary is a list picker control from the silverlight toolkit (you need to download and install the toolkit if you haven’t already). Below it is a textbox where the user can enter words to look up and a button beside it to fetch the word definition when clicked. Finally we have a textblock which occupies the remaining area and displays the word definition from the selected dictionary. Create a silverlight application for windows phone 7, AonawareDictionaryClient, and add references to the silverlight toolkit and the web service. From the solution explorer right on References and select Microsoft.Phone.Controls.Toolkit from under the .NET tab, Next, add a reference to the web service. Again right click on References and this time select Add Service Reference In the resulting dialog paste the service url in the Address field and press go, (url –> http://services.aonaware.com/DictService/DictService.asmx) once the service is discovered, provide a name for the NameSpace, in this case I’ve called it AonawareDictionaryService. Press OK. You can now use the classes and functions that are generated in the AonawareDictionaryClient.AonawareDictionaryService namespace. Let’s get the UI done now. In MainPage.xaml add a namespace declaration to use the toolkit controls, xmlns:toolkit="clr-namespace:Microsoft.Phone.Controls;assembly=Microsoft.Phone.Controls.Toolkit" the content of LayoutRoot is changed as follows, (sorry, no syntax highlighting in this post) <StackPanel x:Name="TitlePanel" Grid.Row="0" Margin="12,5,0,5">     <TextBlock x:Name="ApplicationTitle" Text="AONAWARE DICTIONARY CLIENT" Style="{StaticResource PhoneTextNormalStyle}"/>     <!--<TextBlock x:Name="PageTitle" Text="page name" Margin="9,-7,0,0" Style="{StaticResource PhoneTextTitle1Style}"/>--> </StackPanel> <!--ContentPanel - place additional content here--> <Grid x:Name="ContentPanel" Grid.Row="1" Margin="12,0,12,0">     <Grid.RowDefinitions>         <RowDefinition Height="Auto"/>         <RowDefinition Height="Auto"/>         <RowDefinition Height="*"/>     </Grid.RowDefinitions>     <toolkit:ListPicker Grid.Column="1" x:Name="listPickerDictionaryList"                         Header="Select Dictionary :">     </toolkit:ListPicker>     <Grid Grid.Row="1" Margin="0,5,0,0">         <Grid.ColumnDefinitions>             <ColumnDefinition Width="*"/>             <ColumnDefinition Width="Auto" />         </Grid.ColumnDefinitions>         <TextBox x:Name="txtboxInputWord" Grid.Column="0" GotFocus="OnTextboxInputWordGotFocus" />         <Button x:Name="btnGo" Grid.Column="1" Click="OnButtonGoClick" >             <Button.Content>                 <Image Source="/images/button-go.png"/>             </Button.Content>         </Button>     </Grid>     <ScrollViewer Grid.Row="2" x:Name="scrollViewer">         <TextBlock  Margin="12,5,12,5"  x:Name="txtBlockWordMeaning" HorizontalAlignment="Stretch"                    VerticalAlignment="Stretch" TextWrapping="Wrap"                    FontSize="26" />     </ScrollViewer> </Grid> I have commented out the PageTitle as it occupies too much valuable space, and the ContentPanel is changed to contain three rows. First row contains the list picker control, second row contains the textbox and the button, and the third row contains a textblock within a scroll viewer. The designer will now be showing the final ui, Now go to MainPage.xaml.cs, and add the following namespace declarations, using Microsoft.Phone.Controls; using AonawareDictionaryClient.AonawareDictionaryService; using System.IO.IsolatedStorage; A class called DictServiceSoapClient would have been created for you in the background when you added a reference to the web service. This class functions as a wrapper to the services exported by the web service. All the web service functions that we saw at the start can be access through this class, or more precisely through an object of this class. Create a data member of type DictServiceSoapClient in the Mainpage class, and a function which initializes it, DictServiceSoapClient DictSvcClient = null; private DictServiceSoapClient GetDictServiceSoapClient() {     if (null == DictSvcClient)     {         DictSvcClient = new DictServiceSoapClient();     }     return DictSvcClient; } We have two major tasks remaining. First, when the application loads we need to populate the list picker with all the supported dictionaries and second, when the user enters a word and clicks on the arrow button we need to fetch the word’s meaning. Populating the List Picker In the OnNavigatingTo event of the MainPage, we call the DictionaryList() api. This can also be done in the OnLoading event handler of the MainPage; not sure if one has an advantage over the other. Here’s the code for OnNavigatedTo, protected override void OnNavigatedTo(System.Windows.Navigation.NavigationEventArgs e) {     DictServiceSoapClient client = GetDictServiceSoapClient();     client.DictionaryListCompleted += new EventHandler<DictionaryListCompletedEventArgs>(OnGetDictionaryListCompleted);     client.DictionaryListAsync();     base.OnNavigatedTo(e); } Windows Phone 7 supports only async calls to web services. When we added a reference to the dictionary service, asynchronous versions of all the functions were generated automatically. So in the above function we register a handler to the DictionaryListCompleted event which will occur when the call to DictionaryList() gets a response from the server. Then we call the DictionaryListAsynch() function which is the async version of the DictionaryList() api. The result of this api will be sent to the handler OnGetDictionaryListCompleted(), void OnGetDictionaryListCompleted(object sender, DictionaryListCompletedEventArgs e) {     IsolatedStorageSettings settings = IsolatedStorageSettings.ApplicationSettings;     Dictionary[] listOfDictionaries;     if (e.Error == null)     {         listOfDictionaries = e.Result;         PopulateListPicker(listOfDictionaries, settings);     }     else if (settings.Contains("SavedDictionaryList"))     {         listOfDictionaries = settings["SavedDictionaryList"] as Dictionary[];         PopulateListPicker(listOfDictionaries, settings);     }     else     {         MessageBoxResult res = MessageBox.Show("An error occured while retrieving dictionary list, do you want to try again?", "Error", MessageBoxButton.OKCancel);         if (MessageBoxResult.OK == res)         {             GetDictServiceSoapClient().DictionaryListAsync();         }     }     settings.Save(); } I have used IsolatedStorageSettings to store a few things; the entire dictionary list and the dictionary that is selected when the user exits the application, so that the next time when the user starts the application the current dictionary is set to the last selected value. First we check if the api returned any error, if the error object is null e.Result will contain the list (actually array) of Dictionary type objects. If there was an error, we check the isolated storage settings to see if there is a dictionary list stored from a previous instance of the application and if so, we populate the list picker based on this saved list. Note that in this case there are chances that the dictionary list might be out of date if there have been changes on the server. Finally, if none of these cases are true, we display an error message to the user and try to fetch the list again. PopulateListPicker() is passed the array of Dictionary objects and the settings object as well, void PopulateListPicker(Dictionary[] listOfDictionaries, IsolatedStorageSettings settings) {     listPickerDictionaryList.Items.Clear();     foreach (Dictionary dictionary in listOfDictionaries)     {         listPickerDictionaryList.Items.Add(dictionary.Name);     }     settings["SavedDictionaryList"] = listOfDictionaries;     string savedDictionaryName;     if (settings.Contains("SavedDictionary"))     {         savedDictionaryName = settings["SavedDictionary"] as string;     }     else     {         savedDictionaryName = "WordNet (r) 2.0"; //default dictionary, wordnet     }     foreach (string dictName in listPickerDictionaryList.Items)     {         if (dictName == savedDictionaryName)         {             listPickerDictionaryList.SelectedItem = dictName;             break;         }     }     settings["SavedDictionary"] = listPickerDictionaryList.SelectedItem as string; } We first clear all the items from the list picker, add the dictionary names from the array and then create a key in the settings called SavedDictionaryList and store the dictionary list in it. We then check if there is saved dictionary available from a previous instance, if there is, we set it as the selected item in the list picker. And if not, we set “WordNet ® 2.0” as the default dictionary. Before returning, we save the selected dictionary in the “SavedDictionary” key of the isolated storage settings. Fetching word definitions Getting this part done is very similar to the above code. We get the input word from the textbox, call into DefineInDictAsync() to fetch the definition and when DefineInDictAsync completes, we get the result and display it in the textblock. Here is the handler for the button click, private void OnButtonGoClick(object sender, RoutedEventArgs e) {     txtBlockWordMeaning.Text = "Please wait..";     IsolatedStorageSettings settings = IsolatedStorageSettings.ApplicationSettings;     if (txtboxInputWord.Text.Trim().Length <= 0)     {         MessageBox.Show("Please enter a word in the textbox and press 'Go'");     }     else     {         Dictionary[] listOfDictionaries = settings["SavedDictionaryList"] as Dictionary[];         string selectedDictionary = listPickerDictionaryList.SelectedItem.ToString();         string dictId = "wn"; //default dictionary is wordnet (wn is the dict id)         foreach (Dictionary dict in listOfDictionaries)         {             if (dict.Name == selectedDictionary)             {                 dictId = dict.Id;                 break;             }         }         DictServiceSoapClient client = GetDictServiceSoapClient();         client.DefineInDictCompleted += new EventHandler<DefineInDictCompletedEventArgs>(OnDefineInDictCompleted);         client.DefineInDictAsync(dictId, txtboxInputWord.Text.Trim());     } } We validate the input and then select the dictionary id based on the currently selected dictionary. We need the dictionary id because the api DefineInDict() expects the dictionary identifier and not the dictionary name. We could very well have stored the dictionary id in isolated storage settings too. Again, same as before, we register a event handler for the DefineInDictCompleted event and call the DefineInDictAsync() method passing in the dictionary id and the input word. void OnDefineInDictCompleted(object sender, DefineInDictCompletedEventArgs e) {     WordDefinition wd = e.Result;     scrollViewer.ScrollToVerticalOffset(0.0f);     if (wd.Definitions.Length == 0)     {         txtBlockWordMeaning.Text = String.Format("No definitions were found for '{0}' in '{1}'", txtboxInputWord.Text.Trim(), listPickerDictionaryList.SelectedItem.ToString().Trim());     }     else     {         foreach (Definition def in wd.Definitions)         {             string str = def.WordDefinition;             str = str.Replace("  ", " "); //some formatting             txtBlockWordMeaning.Text = str;         }     } } When the api completes, e.Result will contain a WordDefnition object. This class is also generated in the background while adding the service reference. We check the word definitions within this class to see if any results were returned, if not, we display a message to the user in the textblock. If a definition was found the text on the textblock is set to display the definition of the word. Adding final touches, we now need to save the current dictionary when the application exits. A small but useful thing is selecting the entire word in the input textbox when the user selects it. This makes sure that if the user has looked up a definition for a really long word, he doesn’t have to press ‘clear’ too many times to enter the next word, protected override void OnNavigatingFrom(System.Windows.Navigation.NavigatingCancelEventArgs e) {     IsolatedStorageSettings settings = IsolatedStorageSettings.ApplicationSettings;     settings["SavedDictionary"] = listPickerDictionaryList.SelectedItem as string;     settings.Save();     base.OnNavigatingFrom(e); } private void OnTextboxInputWordGotFocus(object sender, RoutedEventArgs e) {     TextBox txtbox = sender as TextBox;     if (txtbox.Text.Trim().Length > 0)     {         txtbox.SelectionStart = 0;         txtbox.SelectionLength = txtbox.Text.Length;     } } OnNavigatingFrom() is called whenever you navigate away from the MainPage, since our application contains only one page that would mean that it is exiting. I leave you with a short video of the application in action, but before that if you have any suggestions on how to make the code better and improve it please do leave a comment. Until next time…

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  • ASPNET WebAPI REST Guidance

    - by JoshReuben
    ASP.NET Web API is an ideal platform for building RESTful applications on the .NET Framework. While I may be more partial to NodeJS these days, there is no denying that WebAPI is a well engineered framework. What follows is my investigation of how to leverage WebAPI to construct a RESTful frontend API.   The Advantages of REST Methodology over SOAP Simpler API for CRUD ops Standardize Development methodology - consistent and intuitive Standards based à client interop Wide industry adoption, Ease of use à easy to add new devs Avoid service method signature blowout Smaller payloads than SOAP Stateless à no session data means multi-tenant scalability Cache-ability Testability   General RESTful API Design Overview · utilize HTTP Protocol - Usage of HTTP methods for CRUD, standard HTTP response codes, common HTTP headers and Mime Types · Resources are mapped to URLs, actions are mapped to verbs and the rest goes in the headers. · keep the API semantic, resource-centric – A RESTful, resource-oriented service exposes a URI for every piece of data the client might want to operate on. A REST-RPC Hybrid exposes a URI for every operation the client might perform: one URI to fetch a piece of data, a different URI to delete that same data. utilize Uri to specify CRUD op, version, language, output format: http://api.MyApp.com/{ver}/{lang}/{resource_type}/{resource_id}.{output_format}?{key&filters} · entity CRUD operations are matched to HTTP methods: · Create - POST / PUT · Read – GET - cacheable · Update – PUT · Delete - DELETE · Use Uris to represent a hierarchies - Resources in RESTful URLs are often chained · Statelessness allows for idempotency – apply an op multiple times without changing the result. POST is non-idempotent, the rest are idempotent (if DELETE flags records instead of deleting them). · Cache indication - Leverage HTTP headers to label cacheable content and indicate the permitted duration of cache · PUT vs POST - The client uses PUT when it determines which URI (Id key) the new resource should have. The client uses POST when the server determines they key. PUT takes a second param – the id. POST creates a new resource. The server assigns the URI for the new object and returns this URI as part of the response message. Note: The PUT method replaces the entire entity. That is, the client is expected to send a complete representation of the updated product. If you want to support partial updates, the PATCH method is preferred DELETE deletes a resource at a specified URI – typically takes an id param · Leverage Common HTTP Response Codes in response headers 200 OK: Success 201 Created - Used on POST request when creating a new resource. 304 Not Modified: no new data to return. 400 Bad Request: Invalid Request. 401 Unauthorized: Authentication. 403 Forbidden: Authorization 404 Not Found – entity does not exist. 406 Not Acceptable – bad params. 409 Conflict - For POST / PUT requests if the resource already exists. 500 Internal Server Error 503 Service Unavailable · Leverage uncommon HTTP Verbs to reduce payload sizes HEAD - retrieves just the resource meta-information. OPTIONS returns the actions supported for the specified resource. PATCH - partial modification of a resource. · When using PUT, POST or PATCH, send the data as a document in the body of the request. Don't use query parameters to alter state. · Utilize Headers for content negotiation, caching, authorization, throttling o Content Negotiation – choose representation (e.g. JSON or XML and version), language & compression. Signal via RequestHeader.Accept & ResponseHeader.Content-Type Accept: application/json;version=1.0 Accept-Language: en-US Accept-Charset: UTF-8 Accept-Encoding: gzip o Caching - ResponseHeader: Expires (absolute expiry time) or Cache-Control (relative expiry time) o Authorization - basic HTTP authentication uses the RequestHeader.Authorization to specify a base64 encoded string "username:password". can be used in combination with SSL/TLS (HTTPS) and leverage OAuth2 3rd party token-claims authorization. Authorization: Basic sQJlaTp5ZWFslylnaNZ= o Rate Limiting - Not currently part of HTTP so specify non-standard headers prefixed with X- in the ResponseHeader. X-RateLimit-Limit: 10000 X-RateLimit-Remaining: 9990 · HATEOAS Methodology - Hypermedia As The Engine Of Application State – leverage API as a state machine where resources are states and the transitions between states are links between resources and are included in their representation (hypermedia) – get API metadata signatures from the response Link header - in a truly REST based architecture any URL, except the initial URL, can be changed, even to other servers, without worrying about the client. · error responses - Do not just send back a 200 OK with every response. Response should consist of HTTP error status code (JQuery has automated support for this), A human readable message , A Link to a meaningful state transition , & the original data payload that was problematic. · the URIs will typically map to a server-side controller and a method name specified by the type of request method. Stuff all your calls into just four methods is not as crazy as it sounds. · Scoping - Path variables look like you’re traversing a hierarchy, and query variables look like you’re passing arguments into an algorithm · Mapping URIs to Controllers - have one controller for each resource is not a rule – can consolidate - route requests to the appropriate controller and action method · Keep URls Consistent - Sometimes it’s tempting to just shorten our URIs. not recommend this as this can cause confusion · Join Naming – for m-m entity relations there may be multiple hierarchy traversal paths · Routing – useful level of indirection for versioning, server backend mocking in development ASPNET WebAPI Considerations ASPNET WebAPI implements a lot (but not all) RESTful API design considerations as part of its infrastructure and via its coding convention. Overview When developing an API there are basically three main steps: 1. Plan out your URIs 2. Setup return values and response codes for your URIs 3. Implement a framework for your API.   Design · Leverage Models MVC folder · Repositories – support IoC for tests, abstraction · Create DTO classes – a level of indirection decouples & allows swap out · Self links can be generated using the UrlHelper · Use IQueryable to support projections across the wire · Models can support restful navigation properties – ICollection<T> · async mechanism for long running ops - return a response with a ticket – the client can then poll or be pushed the final result later. · Design for testability - Test using HttpClient , JQuery ( $.getJSON , $.each) , fiddler, browser debug. Leverage IDependencyResolver – IoC wrapper for mocking · Easy debugging - IE F12 developer tools: Network tab, Request Headers tab     Routing · HTTP request method is matched to the method name. (This rule applies only to GET, POST, PUT, and DELETE requests.) · {id}, if present, is matched to a method parameter named id. · Query parameters are matched to parameter names when possible · Done in config via Routes.MapHttpRoute – similar to MVC routing · Can alternatively: o decorate controller action methods with HttpDelete, HttpGet, HttpHead,HttpOptions, HttpPatch, HttpPost, or HttpPut., + the ActionAttribute o use AcceptVerbsAttribute to support other HTTP verbs: e.g. PATCH, HEAD o use NonActionAttribute to prevent a method from getting invoked as an action · route table Uris can support placeholders (via curly braces{}) – these can support default values and constraints, and optional values · The framework selects the first route in the route table that matches the URI. Response customization · Response code: By default, the Web API framework sets the response status code to 200 (OK). But according to the HTTP/1.1 protocol, when a POST request results in the creation of a resource, the server should reply with status 201 (Created). Non Get methods should return HttpResponseMessage · Location: When the server creates a resource, it should include the URI of the new resource in the Location header of the response. public HttpResponseMessage PostProduct(Product item) {     item = repository.Add(item);     var response = Request.CreateResponse<Product>(HttpStatusCode.Created, item);     string uri = Url.Link("DefaultApi", new { id = item.Id });     response.Headers.Location = new Uri(uri);     return response; } Validation · Decorate Models / DTOs with System.ComponentModel.DataAnnotations properties RequiredAttribute, RangeAttribute. · Check payloads using ModelState.IsValid · Under posting – leave out values in JSON payload à JSON formatter assigns a default value. Use with RequiredAttribute · Over-posting - if model has RO properties à use DTO instead of model · Can hook into pipeline by deriving from ActionFilterAttribute & overriding OnActionExecuting Config · Done in App_Start folder > WebApiConfig.cs – static Register method: HttpConfiguration param: The HttpConfiguration object contains the following members. Member Description DependencyResolver Enables dependency injection for controllers. Filters Action filters – e.g. exception filters. Formatters Media-type formatters. by default contains JsonFormatter, XmlFormatter IncludeErrorDetailPolicy Specifies whether the server should include error details, such as exception messages and stack traces, in HTTP response messages. Initializer A function that performs final initialization of the HttpConfiguration. MessageHandlers HTTP message handlers - plug into pipeline ParameterBindingRules A collection of rules for binding parameters on controller actions. Properties A generic property bag. Routes The collection of routes. Services The collection of services. · Configure JsonFormatter for circular references to support links: PreserveReferencesHandling.Objects Documentation generation · create a help page for a web API, by using the ApiExplorer class. · The ApiExplorer class provides descriptive information about the APIs exposed by a web API as an ApiDescription collection · create the help page as an MVC view public ILookup<string, ApiDescription> GetApis()         {             return _explorer.ApiDescriptions.ToLookup(                 api => api.ActionDescriptor.ControllerDescriptor.ControllerName); · provide documentation for your APIs by implementing the IDocumentationProvider interface. Documentation strings can come from any source that you like – e.g. extract XML comments or define custom attributes to apply to the controller [ApiDoc("Gets a product by ID.")] [ApiParameterDoc("id", "The ID of the product.")] public HttpResponseMessage Get(int id) · GlobalConfiguration.Configuration.Services – add the documentation Provider · To hide an API from the ApiExplorer, add the ApiExplorerSettingsAttribute Plugging into the Message Handler pipeline · Plug into request / response pipeline – derive from DelegatingHandler and override theSendAsync method – e.g. for logging error codes, adding a custom response header · Can be applied globally or to a specific route Exception Handling · Throw HttpResponseException on method failures – specify HttpStatusCode enum value – examine this enum, as its values map well to typical op problems · Exception filters – derive from ExceptionFilterAttribute & override OnException. Apply on Controller or action methods, or add to global HttpConfiguration.Filters collection · HttpError object provides a consistent way to return error information in the HttpResponseException response body. · For model validation, you can pass the model state to CreateErrorResponse, to include the validation errors in the response public HttpResponseMessage PostProduct(Product item) {     if (!ModelState.IsValid)     {         return Request.CreateErrorResponse(HttpStatusCode.BadRequest, ModelState); Cookie Management · Cookie header in request and Set-Cookie headers in a response - Collection of CookieState objects · Specify Expiry, max-age resp.Headers.AddCookies(new CookieHeaderValue[] { cookie }); Internet Media Types, formatters and serialization · Defaults to application/json · Request Accept header and response Content-Type header · determines how Web API serializes and deserializes the HTTP message body. There is built-in support for XML, JSON, and form-urlencoded data · customizable formatters can be inserted into the pipeline · POCO serialization is opt out via JsonIgnoreAttribute, or use DataMemberAttribute for optin · JSON serializer leverages NewtonSoft Json.NET · loosely structured JSON objects are serialzed as JObject which derives from Dynamic · to handle circular references in json: json.SerializerSettings.PreserveReferencesHandling =    PreserveReferencesHandling.All à {"$ref":"1"}. · To preserve object references in XML [DataContract(IsReference=true)] · Content negotiation Accept: Which media types are acceptable for the response, such as “application/json,” “application/xml,” or a custom media type such as "application/vnd.example+xml" Accept-Charset: Which character sets are acceptable, such as UTF-8 or ISO 8859-1. Accept-Encoding: Which content encodings are acceptable, such as gzip. Accept-Language: The preferred natural language, such as “en-us”. o Web API uses the Accept and Accept-Charset headers. (At this time, there is no built-in support for Accept-Encoding or Accept-Language.) · Controller methods can take JSON representations of DTOs as params – auto-deserialization · Typical JQuery GET request: function find() {     var id = $('#prodId').val();     $.getJSON("api/products/" + id,         function (data) {             var str = data.Name + ': $' + data.Price;             $('#product').text(str);         })     .fail(         function (jqXHR, textStatus, err) {             $('#product').text('Error: ' + err);         }); }            · Typical GET response: HTTP/1.1 200 OK Server: ASP.NET Development Server/10.0.0.0 Date: Mon, 18 Jun 2012 04:30:33 GMT X-AspNet-Version: 4.0.30319 Cache-Control: no-cache Pragma: no-cache Expires: -1 Content-Type: application/json; charset=utf-8 Content-Length: 175 Connection: Close [{"Id":1,"Name":"TomatoSoup","Price":1.39,"ActualCost":0.99},{"Id":2,"Name":"Hammer", "Price":16.99,"ActualCost":10.00},{"Id":3,"Name":"Yo yo","Price":6.99,"ActualCost": 2.05}] True OData support · Leverage Query Options $filter, $orderby, $top and $skip to shape the results of controller actions annotated with the [Queryable]attribute. [Queryable]  public IQueryable<Supplier> GetSuppliers()  · Query: ~/Suppliers?$filter=Name eq ‘Microsoft’ · Applies the following selection filter on the server: GetSuppliers().Where(s => s.Name == “Microsoft”)  · Will pass the result to the formatter. · true support for the OData format is still limited - no support for creates, updates, deletes, $metadata and code generation etc · vnext: ability to configure how EditLinks, SelfLinks and Ids are generated Self Hosting no dependency on ASPNET or IIS: using (var server = new HttpSelfHostServer(config)) {     server.OpenAsync().Wait(); Tracing · tracability tools, metrics – e.g. send to nagios · use your choice of tracing/logging library, whether that is ETW,NLog, log4net, or simply System.Diagnostics.Trace. · To collect traces, implement the ITraceWriter interface public class SimpleTracer : ITraceWriter {     public void Trace(HttpRequestMessage request, string category, TraceLevel level,         Action<TraceRecord> traceAction)     {         TraceRecord rec = new TraceRecord(request, category, level);         traceAction(rec);         WriteTrace(rec); · register the service with config · programmatically trace – has helper extension methods: Configuration.Services.GetTraceWriter().Info( · Performance tracing - pipeline writes traces at the beginning and end of an operation - TraceRecord class includes aTimeStamp property, Kind property set to TraceKind.Begin / End Security · Roles class methods: RoleExists, AddUserToRole · WebSecurity class methods: UserExists, .CreateUserAndAccount · Request.IsAuthenticated · Leverage HTTP 401 (Unauthorized) response · [AuthorizeAttribute(Roles="Administrator")] – can be applied to Controller or its action methods · See section in WebApi document on "Claim-based-security for ASP.NET Web APIs using DotNetOpenAuth" – adapt this to STS.--> Web API Host exposes secured Web APIs which can only be accessed by presenting a valid token issued by the trusted issuer. http://zamd.net/2012/05/04/claim-based-security-for-asp-net-web-apis-using-dotnetopenauth/ · Use MVC membership provider infrastructure and add a DelegatingHandler child class to the WebAPI pipeline - http://stackoverflow.com/questions/11535075/asp-net-mvc-4-web-api-authentication-with-membership-provider - this will perform the login actions · Then use AuthorizeAttribute on controllers and methods for role mapping- http://sixgun.wordpress.com/2012/02/29/asp-net-web-api-basic-authentication/ · Alternate option here is to rely on MVC App : http://forums.asp.net/t/1831767.aspx/1

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  • PTLQueue : a scalable bounded-capacity MPMC queue

    - by Dave
    Title: Fast concurrent MPMC queue -- I've used the following concurrent queue algorithm enough that it warrants a blog entry. I'll sketch out the design of a fast and scalable multiple-producer multiple-consumer (MPSC) concurrent queue called PTLQueue. The queue has bounded capacity and is implemented via a circular array. Bounded capacity can be a useful property if there's a mismatch between producer rates and consumer rates where an unbounded queue might otherwise result in excessive memory consumption by virtue of the container nodes that -- in some queue implementations -- are used to hold values. A bounded-capacity queue can provide flow control between components. Beware, however, that bounded collections can also result in resource deadlock if abused. The put() and take() operators are partial and wait for the collection to become non-full or non-empty, respectively. Put() and take() do not allocate memory, and are not vulnerable to the ABA pathologies. The PTLQueue algorithm can be implemented equally well in C/C++ and Java. Partial operators are often more convenient than total methods. In many use cases if the preconditions aren't met, there's nothing else useful the thread can do, so it may as well wait via a partial method. An exception is in the case of work-stealing queues where a thief might scan a set of queues from which it could potentially steal. Total methods return ASAP with a success-failure indication. (It's tempting to describe a queue or API as blocking or non-blocking instead of partial or total, but non-blocking is already an overloaded concurrency term. Perhaps waiting/non-waiting or patient/impatient might be better terms). It's also trivial to construct partial operators by busy-waiting via total operators, but such constructs may be less efficient than an operator explicitly and intentionally designed to wait. A PTLQueue instance contains an array of slots, where each slot has volatile Turn and MailBox fields. The array has power-of-two length allowing mod/div operations to be replaced by masking. We assume sensible padding and alignment to reduce the impact of false sharing. (On x86 I recommend 128-byte alignment and padding because of the adjacent-sector prefetch facility). Each queue also has PutCursor and TakeCursor cursor variables, each of which should be sequestered as the sole occupant of a cache line or sector. You can opt to use 64-bit integers if concerned about wrap-around aliasing in the cursor variables. Put(null) is considered illegal, but the caller or implementation can easily check for and convert null to a distinguished non-null proxy value if null happens to be a value you'd like to pass. Take() will accordingly convert the proxy value back to null. An advantage of PTLQueue is that you can use atomic fetch-and-increment for the partial methods. We initialize each slot at index I with (Turn=I, MailBox=null). Both cursors are initially 0. All shared variables are considered "volatile" and atomics such as CAS and AtomicFetchAndIncrement are presumed to have bidirectional fence semantics. Finally T is the templated type. I've sketched out a total tryTake() method below that allows the caller to poll the queue. tryPut() has an analogous construction. Zebra stripping : alternating row colors for nice-looking code listings. See also google code "prettify" : https://code.google.com/p/google-code-prettify/ Prettify is a javascript module that yields the HTML/CSS/JS equivalent of pretty-print. -- pre:nth-child(odd) { background-color:#ff0000; } pre:nth-child(even) { background-color:#0000ff; } border-left: 11px solid #ccc; margin: 1.7em 0 1.7em 0.3em; background-color:#BFB; font-size:12px; line-height:65%; " // PTLQueue : Put(v) : // producer : partial method - waits as necessary assert v != null assert Mask = 1 && (Mask & (Mask+1)) == 0 // Document invariants // doorway step // Obtain a sequence number -- ticket // As a practical concern the ticket value is temporally unique // The ticket also identifies and selects a slot auto tkt = AtomicFetchIncrement (&PutCursor, 1) slot * s = &Slots[tkt & Mask] // waiting phase : // wait for slot's generation to match the tkt value assigned to this put() invocation. // The "generation" is implicitly encoded as the upper bits in the cursor // above those used to specify the index : tkt div (Mask+1) // The generation serves as an epoch number to identify a cohort of threads // accessing disjoint slots while s-Turn != tkt : Pause assert s-MailBox == null s-MailBox = v // deposit and pass message Take() : // consumer : partial method - waits as necessary auto tkt = AtomicFetchIncrement (&TakeCursor,1) slot * s = &Slots[tkt & Mask] // 2-stage waiting : // First wait for turn for our generation // Acquire exclusive "take" access to slot's MailBox field // Then wait for the slot to become occupied while s-Turn != tkt : Pause // Concurrency in this section of code is now reduced to just 1 producer thread // vs 1 consumer thread. // For a given queue and slot, there will be most one Take() operation running // in this section. // Consumer waits for producer to arrive and make slot non-empty // Extract message; clear mailbox; advance Turn indicator // We have an obvious happens-before relation : // Put(m) happens-before corresponding Take() that returns that same "m" for T v = s-MailBox if v != null : s-MailBox = null ST-ST barrier s-Turn = tkt + Mask + 1 // unlock slot to admit next producer and consumer return v Pause tryTake() : // total method - returns ASAP with failure indication for auto tkt = TakeCursor slot * s = &Slots[tkt & Mask] if s-Turn != tkt : return null T v = s-MailBox // presumptive return value if v == null : return null // ratify tkt and v values and commit by advancing cursor if CAS (&TakeCursor, tkt, tkt+1) != tkt : continue s-MailBox = null ST-ST barrier s-Turn = tkt + Mask + 1 return v The basic idea derives from the Partitioned Ticket Lock "PTL" (US20120240126-A1) and the MultiLane Concurrent Bag (US8689237). The latter is essentially a circular ring-buffer where the elements themselves are queues or concurrent collections. You can think of the PTLQueue as a partitioned ticket lock "PTL" augmented to pass values from lock to unlock via the slots. Alternatively, you could conceptualize of PTLQueue as a degenerate MultiLane bag where each slot or "lane" consists of a simple single-word MailBox instead of a general queue. Each lane in PTLQueue also has a private Turn field which acts like the Turn (Grant) variables found in PTL. Turn enforces strict FIFO ordering and restricts concurrency on the slot mailbox field to at most one simultaneous put() and take() operation. PTL uses a single "ticket" variable and per-slot Turn (grant) fields while MultiLane has distinct PutCursor and TakeCursor cursors and abstract per-slot sub-queues. Both PTL and MultiLane advance their cursor and ticket variables with atomic fetch-and-increment. PTLQueue borrows from both PTL and MultiLane and has distinct put and take cursors and per-slot Turn fields. Instead of a per-slot queues, PTLQueue uses a simple single-word MailBox field. PutCursor and TakeCursor act like a pair of ticket locks, conferring "put" and "take" access to a given slot. PutCursor, for instance, assigns an incoming put() request to a slot and serves as a PTL "Ticket" to acquire "put" permission to that slot's MailBox field. To better explain the operation of PTLQueue we deconstruct the operation of put() and take() as follows. Put() first increments PutCursor obtaining a new unique ticket. That ticket value also identifies a slot. Put() next waits for that slot's Turn field to match that ticket value. This is tantamount to using a PTL to acquire "put" permission on the slot's MailBox field. Finally, having obtained exclusive "put" permission on the slot, put() stores the message value into the slot's MailBox. Take() similarly advances TakeCursor, identifying a slot, and then acquires and secures "take" permission on a slot by waiting for Turn. Take() then waits for the slot's MailBox to become non-empty, extracts the message, and clears MailBox. Finally, take() advances the slot's Turn field, which releases both "put" and "take" access to the slot's MailBox. Note the asymmetry : put() acquires "put" access to the slot, but take() releases that lock. At any given time, for a given slot in a PTLQueue, at most one thread has "put" access and at most one thread has "take" access. This restricts concurrency from general MPMC to 1-vs-1. We have 2 ticket locks -- one for put() and one for take() -- each with its own "ticket" variable in the form of the corresponding cursor, but they share a single "Grant" egress variable in the form of the slot's Turn variable. Advancing the PutCursor, for instance, serves two purposes. First, we obtain a unique ticket which identifies a slot. Second, incrementing the cursor is the doorway protocol step to acquire the per-slot mutual exclusion "put" lock. The cursors and operations to increment those cursors serve double-duty : slot-selection and ticket assignment for locking the slot's MailBox field. At any given time a slot MailBox field can be in one of the following states: empty with no pending operations -- neutral state; empty with one or more waiting take() operations pending -- deficit; occupied with no pending operations; occupied with one or more waiting put() operations -- surplus; empty with a pending put() or pending put() and take() operations -- transitional; or occupied with a pending take() or pending put() and take() operations -- transitional. The partial put() and take() operators can be implemented with an atomic fetch-and-increment operation, which may confer a performance advantage over a CAS-based loop. In addition we have independent PutCursor and TakeCursor cursors. Critically, a put() operation modifies PutCursor but does not access the TakeCursor and a take() operation modifies the TakeCursor cursor but does not access the PutCursor. This acts to reduce coherence traffic relative to some other queue designs. It's worth noting that slow threads or obstruction in one slot (or "lane") does not impede or obstruct operations in other slots -- this gives us some degree of obstruction isolation. PTLQueue is not lock-free, however. The implementation above is expressed with polite busy-waiting (Pause) but it's trivial to implement per-slot parking and unparking to deschedule waiting threads. It's also easy to convert the queue to a more general deque by replacing the PutCursor and TakeCursor cursors with Left/Front and Right/Back cursors that can move either direction. Specifically, to push and pop from the "left" side of the deque we would decrement and increment the Left cursor, respectively, and to push and pop from the "right" side of the deque we would increment and decrement the Right cursor, respectively. We used a variation of PTLQueue for message passing in our recent OPODIS 2013 paper. ul { list-style:none; padding-left:0; padding:0; margin:0; margin-left:0; } ul#myTagID { padding: 0px; margin: 0px; list-style:none; margin-left:0;} -- -- There's quite a bit of related literature in this area. I'll call out a few relevant references: Wilson's NYU Courant Institute UltraComputer dissertation from 1988 is classic and the canonical starting point : Operating System Data Structures for Shared-Memory MIMD Machines with Fetch-and-Add. Regarding provenance and priority, I think PTLQueue or queues effectively equivalent to PTLQueue have been independently rediscovered a number of times. See CB-Queue and BNPBV, below, for instance. But Wilson's dissertation anticipates the basic idea and seems to predate all the others. Gottlieb et al : Basic Techniques for the Efficient Coordination of Very Large Numbers of Cooperating Sequential Processors Orozco et al : CB-Queue in Toward high-throughput algorithms on many-core architectures which appeared in TACO 2012. Meneghin et al : BNPVB family in Performance evaluation of inter-thread communication mechanisms on multicore/multithreaded architecture Dmitry Vyukov : bounded MPMC queue (highly recommended) Alex Otenko : US8607249 (highly related). John Mellor-Crummey : Concurrent queues: Practical fetch-and-phi algorithms. Technical Report 229, Department of Computer Science, University of Rochester Thomasson : FIFO Distributed Bakery Algorithm (very similar to PTLQueue). Scott and Scherer : Dual Data Structures I'll propose an optimization left as an exercise for the reader. Say we wanted to reduce memory usage by eliminating inter-slot padding. Such padding is usually "dark" memory and otherwise unused and wasted. But eliminating the padding leaves us at risk of increased false sharing. Furthermore lets say it was usually the case that the PutCursor and TakeCursor were numerically close to each other. (That's true in some use cases). We might still reduce false sharing by incrementing the cursors by some value other than 1 that is not trivially small and is coprime with the number of slots. Alternatively, we might increment the cursor by one and mask as usual, resulting in a logical index. We then use that logical index value to index into a permutation table, yielding an effective index for use in the slot array. The permutation table would be constructed so that nearby logical indices would map to more distant effective indices. (Open question: what should that permutation look like? Possibly some perversion of a Gray code or De Bruijn sequence might be suitable). As an aside, say we need to busy-wait for some condition as follows : "while C == 0 : Pause". Lets say that C is usually non-zero, so we typically don't wait. But when C happens to be 0 we'll have to spin for some period, possibly brief. We can arrange for the code to be more machine-friendly with respect to the branch predictors by transforming the loop into : "if C == 0 : for { Pause; if C != 0 : break; }". Critically, we want to restructure the loop so there's one branch that controls entry and another that controls loop exit. A concern is that your compiler or JIT might be clever enough to transform this back to "while C == 0 : Pause". You can sometimes avoid this by inserting a call to a some type of very cheap "opaque" method that the compiler can't elide or reorder. On Solaris, for instance, you could use :"if C == 0 : { gethrtime(); for { Pause; if C != 0 : break; }}". It's worth noting the obvious duality between locks and queues. If you have strict FIFO lock implementation with local spinning and succession by direct handoff such as MCS or CLH,then you can usually transform that lock into a queue. Hidden commentary and annotations - invisible : * And of course there's a well-known duality between queues and locks, but I'll leave that topic for another blog post. * Compare and contrast : PTLQ vs PTL and MultiLane * Equivalent : Turn; seq; sequence; pos; position; ticket * Put = Lock; Deposit Take = identify and reserve slot; wait; extract & clear; unlock * conceptualize : Distinct PutLock and TakeLock implemented as ticket lock or PTL Distinct arrival cursors but share per-slot "Turn" variable provides exclusive role-based access to slot's mailbox field put() acquires exclusive access to a slot for purposes of "deposit" assigns slot round-robin and then acquires deposit access rights/perms to that slot take() acquires exclusive access to slot for purposes of "withdrawal" assigns slot round-robin and then acquires withdrawal access rights/perms to that slot At any given time, only one thread can have withdrawal access to a slot at any given time, only one thread can have deposit access to a slot Permissible for T1 to have deposit access and T2 to simultaneously have withdrawal access * round-robin for the purposes of; role-based; access mode; access role mailslot; mailbox; allocate/assign/identify slot rights; permission; license; access permission; * PTL/Ticket hybrid Asymmetric usage ; owner oblivious lock-unlock pairing K-exclusion add Grant cursor pass message m from lock to unlock via Slots[] array Cursor performs 2 functions : + PTL ticket + Assigns request to slot in round-robin fashion Deconstruct protocol : explication put() : allocate slot in round-robin fashion acquire PTL for "put" access store message into slot associated with PTL index take() : Acquire PTL for "take" access // doorway step seq = fetchAdd (&Grant, 1) s = &Slots[seq & Mask] // waiting phase while s-Turn != seq : pause Extract : wait for s-mailbox to be full v = s-mailbox s-mailbox = null Release PTL for both "put" and "take" access s-Turn = seq + Mask + 1 * Slot round-robin assignment and lock "doorway" protocol leverage the same cursor and FetchAdd operation on that cursor FetchAdd (&Cursor,1) + round-robin slot assignment and dispersal + PTL/ticket lock "doorway" step waiting phase is via "Turn" field in slot * PTLQueue uses 2 cursors -- put and take. Acquire "put" access to slot via PTL-like lock Acquire "take" access to slot via PTL-like lock 2 locks : put and take -- at most one thread can access slot's mailbox Both locks use same "turn" field Like multilane : 2 cursors : put and take slot is simple 1-capacity mailbox instead of queue Borrow per-slot turn/grant from PTL Provides strict FIFO Lock slot : put-vs-put take-vs-take at most one put accesses slot at any one time at most one put accesses take at any one time reduction to 1-vs-1 instead of N-vs-M concurrency Per slot locks for put/take Release put/take by advancing turn * is instrumental in ... * P-V Semaphore vs lock vs K-exclusion * See also : FastQueues-excerpt.java dice-etc/queue-mpmc-bounded-blocking-circular-xadd/ * PTLQueue is the same as PTLQB - identical * Expedient return; ASAP; prompt; immediately * Lamport's Bakery algorithm : doorway step then waiting phase Threads arriving at doorway obtain a unique ticket number Threads enter in ticket order * In the terminology of Reed and Kanodia a ticket lock corresponds to the busy-wait implementation of a semaphore using an eventcount and a sequencer It can also be thought of as an optimization of Lamport's bakery lock was designed for fault-tolerance rather than performance Instead of spinning on the release counter, processors using a bakery lock repeatedly examine the tickets of their peers --

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