PM22729: Memory Leak with XMLStreamReader may lead to OutOfMemoryError

6.1.0.37: Java SDK 1.5 SR12 FP3 Cumulative Fix for WebSphere
6.1.0.47: WebSphere Application Server V6.1 Fix Pack 47
6.1.0.39: Java SDK 1.5 SR12 FP4 Cumulative Fix for WebSphere Application Server
6.1.0.41: Java SDK 1.5 SR12 FP5 Cumulative Fix for WebSphere Application Server
6.1.0.43: Java SDK 1.5 SR13 Cumulative Fix for WebSphere Application Server
6.1.0.45: Java SDK 1.5 SR14 Cumulative Fix for WebSphere Application Server
6.1.0.47: Java SDK 1.5 SR16 Cumulative Fix for WebSphere Application Server

APAR status

• Closed as program error.

Error description

• A memory leak in the JAX-WS runtime may lead to a
  java.lang.OutOfMemoryError. A tremendous growth in the
  number of XMLStreamReaderImpl objects on the heap will be seen.
  Here is a sample heapdump that was collected during a stress
  test:
  
  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
  

Local fix

Problem summary

• ****************************************************************
  * USERS AFFECTED:  All users of IBM WebSphere Application      *
  *                  Server Feature Pack for Web Services        *
  *                  JAX-WS applications                         *
  ****************************************************************
  * PROBLEM DESCRIPTION: A memory leak with XMLStreamReaders     *
  *                      objects may lead to an                  *
  *                      OutOfMemoryError.                       *
  ****************************************************************
  * RECOMMENDATION:  Install a fix pack that contains this APAR. *
  *                                                              *
  ****************************************************************
  When running JAX-WS applications, a tremendous growth in
  the number of XMLStreamReaderImpl objects in the heap may be
  observed.
  A heapdump collected from a stress test may look
  like the following:
  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
  

Problem conclusion

• Within the JAX-WS runtime, XMLStreamReaders are used for
  processing Web services messages. Occasionally these objects
  are not properly closed by the JAX-WS runtime, preventing them
  from being reused and garbage collected, leading to an
  OutOfMemoryError after a large number of requests.
  
  A system property called
  com.ibm.xml.xlxp.api.util.UnsynchronizedBag.MAXIMUM_SIZE is
  provided by this APAR. Its value is an integer and when set,
  it limits the size of the pools used for caching
  XMLStreamReaders (and XMLStreamWriters).
  
  To avoid the OutOfMemoryError, set the system property to a
  small value (for example, 2 or 5). When the system property is
  not set, the size of the pools is unbounded by default.
  
  For information on setting properties, refer to the
  Information Center article titled "Java virtual machine custom
  properties" for your version and release of WebSphere
  Application Server.
  
  The fix for this APAR is currently targeted for inclusion in
  fix pack 6.1.0.37.  Please refer to the Recommended Updates
  page for delivery information:
  http://www.ibm.com/support/docview.wss?rs=180&uid=swg27004980
  
  Note that this fix is for base enablement in WebSphere
  Application Server to fix the problem observed in the Feature
  Pack for Web Services.
  

Temporary fix

Comments

APAR Information

• APAR is sysrouted FROM one or more of the following:

• APAR is sysrouted TO one or more of the following:

Fix information

• Fixed component name

  WEBSPHERE APP S

• Fixed component ID

  5724J0800

Applicable component levels

• R61A PSY

     UP

• R61H PSY

     UP

• R61I PSY

     UP

• R61P PSY

     UP

• R61S PSY

     UP

• R61W PSY

     UP

• R61Z PSY

     UP