PH39981: JVM MBEAN DUMPTHREADS() CAN CREATE HEAP OR SYSTEM CORE DUMPS

APAR status

• Closed as program error.

Error description

• On non-Windows platforms, if Java dump handlers are configured t
  trigger heap and/or core dumps on user dump events, the JVM
  MBean's dumpThreads() method will create these dumps in addition
  to the requested thread dump
  

Local fix

Problem summary

• ****************************************************************
  * USERS AFFECTED:  All users of IBM WebSphere Application      *
  *                  Server                                      *
  ****************************************************************
  * PROBLEM DESCRIPTION: The dumpThreads() method of the WAS JVM *
  *                      MBean can trigger other dump handlers   *
  ****************************************************************
  * RECOMMENDATION:                                              *
  ****************************************************************
  The WAS JVM MBean provides a dumpThreads() method that's
  intended
  to create a thread dump of the JVM. However, due to the way that
  this method is currently implemented on non-Windows platforms,
  it
  will trigger all dump handlers that are configured on user dump
  events. This can be a problem if more heavyweight dumps (such as
  heap or system core dumps) are configured for these events, as
  there is no way to effectively get thread dumps alone.
  

Problem conclusion

• The JVMMBean.dumpThreads() was modified to utilize the IBM J9
  JVM's JavaDump class to create a javacore (the intended output
  of a thread dump request) on supported platforms. Non-IBM JVM
  platforms (Solaris and HP-UX) will retain the legacy behavior,
  triggering thread dumps by signaling the process.
  
  The fix for this APAR is targeted for inclusion in fix packs
  9.0.5.13 and 8.5.5.22. For more information, see 'Recommended
  Updates for WebSphere Application Server':
  https://www.ibm.com/support/pages/node/715553
  

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