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IJ12109: PERFORMANCE REGRESSION OF ABOUT 2%-6%

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APAR status

  • Closed as program error.

Error description

  • Error Message: Performance regression is seen on varies
    benchmarks on all platforms for about 2%-6%.
    .
    Stack Trace: N/A
    .
    

Local fix

  • Use the Java option -XX:-EnableHCR to disable bytecode
    instrumentation. Notice this could result in Java agent not
    working properly.
    

Problem summary

  • The regression resulted from an attempt to trigger
    recompilations for methods whose callees get redefined. The
    extra calls to trigger recompilation are inserted into multiple
    places in generated code in most of the compiled methods. This
    increases the size of the code cache and results in performance
    regression.
    

Problem conclusion

  • The source code has been updated to avoid inserting extra calls
    to trigger recompilation.
    .
    This APAR will be fixed in the following Java Releases:
       8    SR5 FP27  (8.0.5.27)
    .
    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 number

    IJ12109

  • Reported component name

    JIT

  • Reported component ID

    620700124

  • Reported release

    130

  • Status

    CLOSED PER

  • PE

    NoPE

  • HIPER

    NoHIPER

  • Special Attention

    NoSpecatt / Xsystem

  • Submitted date

    2018-12-11

  • Closed date

    2018-12-11

  • Last modified date

    2018-12-11

  • 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

[{"Business Unit":{"code":"BU048","label":"IBM Software"},"Product":{"code":"SSC9HBA","label":"Just In Time (JIT) Compiler"},"Component":"","ARM Category":[],"Platform":[{"code":"PF025","label":"Platform Independent"}],"Version":"130","Edition":"","Line of Business":{"code":"","label":""}}]

Document Information

Modified date:
11 December 2018