axis2 leading to JVM , outOfMemory

[K Srinivasan]

hi,
we have a web service call on one of our application layers.
we are using WAS 6.1 and Apace Axis2 1.5 ,
The problem is that the memory used by JVM keeps on increasing , finally leading to a restart of the JVM,
On analysing the heap dump , the problem was found to be with the following classes :

com.ibm.xml.xlxp.api.stax.xml.streamReaderImplementation
and com.ibm.xlxp.api.util.UnSynchronizedBag.

Is this a bug with the Axis2 ?

Any help would be appreciated.

[Jimmy Clark]

Sound like it could be a bug in your web service. Are the application server and the Axis engine running in the same JRE?

[K Srinivasan]

yes they are on the same jre.
Well, the same code is running on a different project without issues, so i guess shouldn't be an issue with the code

[Lester Burnham]

What do you mean by "the problem was found to be with the following classes" - what did the heap dump analysis tell you?

[K Srinivasan]

Hi,

tthe heap dump analysis shows a memory leak due to the
com.ibm.xml.xlxp.api.stax.xml.streamReaderImplementation
and com.ibm.xlxp.api.util.UnSynchronizedBag.



641,360 (0%) [336] 38 com/ibm/xml/xlxp/api/stax/XMLStreamReaderImpl
0xa4fd1918
25,216 (0%) [280] 29 com/ibm/xml/xlxp/api/stax/StAXDTDScanner
0xa58a49e0
641,360 (0%) [336] 38 com/ibm/xml/xlxp/api/stax/XMLStreamReaderImpl
0xa4fd1918

[Lester Burnham]

I have no idea what those numbers mean (maybe you meant to explain them?), but "0%" doesn't sound problematic.

[subodh k kumar]

What is the heap size defined in your project . Is it the same as other project ? i think provided logs are not good enough to suggest any thing.please provide more log.

[K Srinivasan]

@Lester :

I reviewed the heap dump again ,
there are instances of com.ibm.xlxp.api.util.UnSynchronizedBag which consume about 10% of the heap.

This is a analysis is by the App Server Vendor :
build up of XMLStreamReader instances in UnsynchronizedBag is usually a sign that the component(s) using StAX are failing to call close() on them. In the WSFP, calling close() on XMLStreamReader instances is a hard requirement. Failure to call close() may result in a leak.


@subodh
The heap size is same.
The intial heap size is 512MB and Max Heap size is 1024 MB
The heap size keep on increasing even after gc.
What other logs do you need ??

Thanks

[Lester Burnham]

This is odd - Axis2 comes with its own StAX implementation (in the com/ctc/wstx and org/codehaus/stax2 packages), so I wouldn't think that it uses IBM's implementation.

[K Srinivasan]

@Burnham
yeah , we weren't using the stax jar, so it was using the one from IBM,
the problem seems to be resolved after using
geronimo-stax-api_1.0_spec



Thanks