IT25470: FILEOUTPUT NODE LEAKS NATIVE MEMORY VIA JAVA

APAR status

• Closed as program error.

Error description

• When a FileOutput node is used, small Java objects are
  allocated which own references to large natively allocated
  objects. Since these Java objects are small they are
  infrequently garbage collected which results in the large
  native objects persisting for long durations. Under load this
  can appear as a steadily growing memory usage which sometimes
  decreases once a JVM GC is triggered. The Java heap size does
  not grow discernibly during this leak.
  

Local fix

• NA
  

Problem summary

• ****************************************************************
  USERS AFFECTED:
  All users of IBM Integration Bus v10 and IBM App Connect
  Enterprise v11 who use the FileOutput node.		
  
  
  Platforms affected:
  z/OS, MultiPlatform
  
  ****************************************************************
  PROBLEM DESCRIPTION:
  The FileOutput node can leak memory associated with XPath
  expressions, this can lead to unexpected process growth in the
  DataFlowEngine or IntegrationServer processes.
  
  The FileOutput node, which is implemented in Java, allocates a
  large chunk of a native memory via a small Java object to handle
  parsing XPath attributes on the node each time a file is sent.
  When the data is sent it is left to the Java GC to clean up
  these objects. Since the Java object is a thin wrapper the JVM
  thinks the memory used by it is small and may delay freeing it
  which can lead to a buildup of large native memory being wasted
  waiting for the JVM to clean up the thin wrappers.
  

Problem conclusion

• The FileOutput node now explicitly frees this native memory
  after it has finished sending a file.
  
  ---------------------------------------------------------------
  The fix is targeted for delivery in the following PTFs:
  
  Version    Maintenance Level
  v10.0      10.0.0.14
  v11.0      11.0.0.2
  
  The latest available maintenance can be obtained from:
  http://www-01.ibm.com/support/docview.wss?rs=849&uid=swg27006041
  
  If the maintenance level is not yet available,information on
  its planned availability can be found on:
  http://www-1.ibm.com/support/docview.wss?rs=849&uid=swg27006308
  ---------------------------------------------------------------
  

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

  INTEGRATION BUS

• Fixed component ID

  5724J0540

Applicable component levels