perfsonar development work

["Michael Bischoff" <>]

also see http://java.sun.com/developer/technicalArticles/J2SE/monitoring/

> Hello all,
>
>
> Sounds like a memory leak(as in unnecessary references to objects that 
> won't be used any
> more are bening kept) in one of the applications, try using the management 
> console to find
> out which project is the culprit or else profile the application and track 
> live objects.
>
> temp workaround would be to start the jvm with additional varargs.
>
> -Xms512m
> -Xmx1024m
> -XX:PermSize=512m
> -XX:MaxPermSize=1024m
>
>
> these values are probably ridiculous normal app so tweak it.
>
> a note about these: "    * Options that begin with -X are non-standard (not 
> guaranteed to be
> supported on all VM implementations), and are subject to change without 
> notice in subsequent
> releases of the JDK. * Options that are specified with -XX are not stable 
> and are not
> recommended for casual use. These options are subject to change without 
> notice."
>
> but you should probably take that with a pinch of salt -XX:PermSize works 
> for as log as I
> remember. (on sun jvm's)
>
> Also mind that after a error is thrown the jvm can't guarantee correct 
> behaviour any more,
> so the first error message is probably bogus.
>
> I hope this helps,
>
>
> Best regards,
>
>
> Michael Bischoff
>
>
>> Dear Perfsonar Developers,
>>
>>
>>
>> I would like to share with you a temporal error message (or problem)
>> that might be due to some recently installed services on URAN.
>>
>> So far we have LS, hLS, gLS, RRD MA and SQL MA on uran.acad.bg. During
>> some tests today Stijn reported the following eXist error message:
>>
>> --------------------------------------
>> XML Parsing Error: no element found
>> Location: http://uran.acad.bg:8080/exist/index.xml
>> Line Number 1, Column 1:
>> ^
>> --------------------------------------
>>
>>
>>
>> while tomcat log files were full of the following:
>>
>> --------------------------------------
>> ...
>> SEVERE: Servlet.service() for servlet Cocoon threw exception
>> java.lang.OutOfMemoryError: PermGen space
>> Jun 5, 2008 4:47:14 PM org.apache.catalina.core.StandardWrapperValve invoke
>> SEVERE: Servlet.service() for servlet XQueryServlet threw exception
>> java.lang.OutOfMemoryError: PermGen space
>> Jun 5, 2008 4:48:34 PM org.apache.catalina.core.ApplicationContext log
>> SEVERE: Servlet jsp threw unload() exception
>> ...
>> --------------------------------------
>>
>>
>>
>> In addition the normal procedure of shutting down tomcat with
>> tomcat/bin/shutdown.sh took some minutes (check top.png).
>>
>> It would be great if you could provide any tips on how to avoid such
>> errors in future.
>>
>> Kind regards,
>>
>>
>>
>> Atanas
>>
>>
>>
>
>