PI25397: INTERMITTENT CONNECTION LEAK WHEN HANDLING MTOM ATTACHMENT RESPONSES WITH EXTRA CHARACTERS AT THE END

8.0.0.10: WebSphere Application Server V8.0 Fix Pack 10
8.0.0.11: WebSphere Application Server V8.0 Fix Pack 11
8.0.0.12: WebSphere Application Server V8.0 Fix Pack 12
8.0.0.13: WebSphere Application Server V8.0 Fix Pack 13
8.0.0.14: WebSphere Application Server V8.0 Fix Pack 14
8.0.0.15: WebSphere Application Server V8.0 Fix Pack 15

APAR status

• Closed as program error.

Error description

• Web services outbound connection pool may leak connections
  intermittently when handling MTOM attachment responses with
  extra characters. No exceptions or ffdc are observed when
  connections start leaking.
  

Local fix

• Increase maximum web service connection pool size to reduce
  impact and restart application servers based on load and usage
  of connection pool.
  

Problem summary

• ****************************************************************
  * USERS AFFECTED:  IBM WebSphere Application Server V8.0 and   *
  *                  V8.5 users of JAX-WS web services           *
  ****************************************************************
  * PROBLEM DESCRIPTION: A connection is not correctly closed    *
  *                      when normal MTOM attachment in the      *
  *                      response is followed by extra           *
  *                      meaningless characters.                 *
  ****************************************************************
  * RECOMMENDATION:                                              *
  ****************************************************************
  During the MTOM response unmarshalling, multiple unmarshallers
  are involved in reading in parts of the response message to
  unmarshall. The marshaller will recognize the normal end of
  the MTOM attachment(Mime boundary). Any other characters after
  that will treated as useless, and will not be read in for
  unmarshalling or further processing. This causes the buffer
  to not be fully read, hence the connection cannot be closed.
  

Problem conclusion

• Code is modified to trigger more readBuffer operations at the
  end of processing of the JAX-WS MTOM Response, to make sure
  the connection can be discarded or reset for reuse.
  
  By default, this machanism is enabled, and we only read 5
  more times. If the buffer is still not empty, the connection
  will be discarded. If the buffer can be read out within 5
  calls to readBuffer, the connection will be reset for reuse.
  
  To disable this machanism, you need to add a new JVM property:
  com.ibm.ws.websvcs.additionalBufferReadTimes, and set its
  value to 0.
  
  You can also tune this property as you needed, please note the
  value of this property should be a positive integer or zero.
  
  The fix for this APAR is currently targeted for inclusion in
  fix packs 8.0.0.10 and 8.5.5.6.  Please refer to the
  Recommended Updates page for delivery information:
  http://www.ibm.com/support/docview.wss?rs=180&uid=swg27004980
  

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

  WEBS APP SERV N

• Fixed component ID

  5724H8800

Applicable component levels

• R800 PSY

     UP

• R850 PSY

     UP