IV72385: JIT COMPILED METHOD INITIALLY USES A GPU BUT STOPS LATER ON

APAR status

• Closed as program error.

Error description

• Error Message: When the -Xjit:enableGPU={verbose} option is
  used, messages indicating GPU use are printed to
  console.Eg.(...) Launching parallel forEach in (...)When the
  error occurs, these messages stop appearing even when the
  expectation is the method is still being run and should still be
  using the GPU.
  .
  Stack Trace: N/A
  .
  

Local fix

• Force the method that uses a GPU to be compiled at the hot
  optimization
  level.-Xjit:{gpu/Method.name(II)I}(optLevel=hot)"gpu/Method.name
  (II)I" should be replaced with the real method name.
  

Problem summary

• The method was recompiled at a hotness level that does not
  generate GPU code. The result was after recompilation the method
  would no longer use a GPU when run.
  

Problem conclusion

• Methods that qualify for generating GPU code can now do so even
  at higher hotness levels.
  .
  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:

Fix information

• Fixed component name

  JIT

• Fixed component ID

  620700124

Applicable component levels

• R130 PSY

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