IV92797: DTFJ MAY IMPROPERLY REPORT THE SIZE OF LARGE ARRAYS WHEN USING THE BALANCED GC POLICY.

APAR status

• Closed as program error.

Error description

• Error Message: N/A
  .
  Stack Trace: N/A
  .
  Tools such as jdmpview and Memory Analyzer that use
  com.ibm.dtfj.java.JavaObject#getSize() report only the size of
  the 'spine' for large arrays under the 'balanced' GC policy. The
  total heap space use computed this way disagrees with
  information captured in javacore files.
  

Local fix

• No known workaround exists.
  

Problem summary

• The implementations of com.ibm.dtfj.java.JavaObject#getSize()
  report only the size of the 'spine' for large arrays under the
  'balanced' GC policy. Totals computed via this API
  under-estimate the actual heap space usage which disagree with
  information captured in javacore files.
  

Problem conclusion

• The DTFJ implementation has been corrected to include all space
  occupied by arrays for all GC policies.
  .
  This APAR will be fixed in the following Java Releases:
     8    SR4 FP1   (8.0.4.1)
     7 R1 SR4 FP5   (7.1.4.5)
  .
  Contact your IBM Product's Service Team for these Service
  Refreshes and Fix Packs.
  For those running stand-alone, information about the available
  Service Refreshes and Fix Packs can be found at:
             https://www.ibm.com/developerworks/java/jdk/
  

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

  J9 COMMON CODE

• Fixed component ID

  620700127

Applicable component levels

• R270 PSY

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