Changes for page Troubleshooting Frozen Deployed Instances
Last modified by David Avendasora on 2010/11/30 06:43
From version 12.1
edited by Pascal Robert
on 2007/09/03 22:05
on 2007/09/03 22:05
Change comment:
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To version 15.1
edited by David Avendasora
on 2010/11/30 06:42
on 2010/11/30 06:42
Change comment:
There is no comment for this version
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... ... @@ -1,1 +1,1 @@ 1 - WebApplications-Deployment-Debugging Frozen Deployed Instances1 +Troubleshooting Frozen Deployed Instances - Author
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... ... @@ -1,1 +1,1 @@ 1 -XWiki. probert1 +XWiki.avendasora - Content
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... ... @@ -56,6 +56,14 @@ 56 56 57 57 Now restart your instances. 58 58 59 +Note that some JVM's on other platforms expect the "jdwp" to be specified as follows; 60 + 61 +{{noformat}} 62 + 63 +-agentlib:jdwp=transport=dt_socket,address=8121,server=y,suspend 64 + 65 +{{/noformat}} 66 + 59 59 = When Something Goes Wrong... = 60 60 61 61 The instances are listed in the JavaMonitor. A screenshot is shown below with the instance number circled in red. You need to first identify which instance has frozen. ... ... @@ -86,6 +86,20 @@ 86 86 87 87 = What to Look For = 88 88 97 +##jdb##'s ##watch all## command will give you a stack trace for all threads in your app. But your process needs first to be suspended in order to get a coherent stack trace. Use it like so: 98 + 99 +{{noformat}} 100 + 101 +> suspend 102 +All threads suspended. 103 +> where all 104 +... 105 +> resume 106 +All threads resumed. 107 +> 108 + 109 +{{/noformat}} 110 + 89 89 An example of a stack trace is shown below. You'll notice the java class name and source-code line number at the end of a particular entry in the stack. Here we can see that the thread called "WorkerThread103" has stuck trying to get a session from the session store. In this situation another thread will most likely have the session store locked and is not releasing the lock. 90 90 91 91 {{noformat}} ... ... @@ -120,3 +120,7 @@ 120 120 = Conclusion = 121 121 122 122 Despite the simplicity of this approach, it provides for a means by which you can find out what is going on inside frozen instances rather than playing laborious guessing games. 145 + 146 += Alternative Approaches = 147 + 148 +[[http://www.gvcsitemaker.com/gvc.webobjects/faq&mode=single&recordID=41413]]