IV72334: POOR PERFORMANCE ON METHODS MANIPULATING MANY ARRAYS

APAR status

• Closed as program error.

Error description

• Error Message: None
  .
  Stack Trace:
  .
  Methods that manipulate an unusually large number of arrays
  (several dozen) within loops can suffer poor performance because
  the method will not be jit-compiled.
  

Local fix

• -Xjit:disableInternalPointers
  

Problem summary

• The JIT compiler contains an internal check to ensure that a
  particular design limit is not exceeded, and if it is exceeded,
  the compiled method is discarded, and the method is executed by
  the interpreter (or is compiled at a lower optimization level).
  The problem is that the limit value used for this check was
  smaller than necessary, causing valid compiled methods to be
  needlessly discarded.
  

Problem conclusion

• The JIT compiler was modified to check the correct limit value.
  .
  This APAR will be fixed in the following Java Releases:
   8 SR1 (8.0.1.0)
  .
  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:

• Fixed component name

  JIT

• Fixed component ID

  620700124

Applicable component levels

• R130 PSY

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