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IV94294: INCREASE IN NUMBER OF SYSTEM.GC() CALLS AT CERTAIN WORKLOADS AFTER APPLYING IV68743

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You can track all active APARs for this component.

 

APAR status

  • Closed as program error.

Error description

  • Error Message: Sudden jump in the use of DirectByteBuffers may
    see an increase in the number of System.gc() calls after
    applying IV68743.
    .
    Stack Trace: The System.gc() calls are triggered by this stack:
    java/lang/System.gc()
    java/nio/Bits.reserveMemory()
    java/nio/DirectByteBuffer.<init>()
    java/nio/ByteBuffer.allocateDirect()
    .
    

Local fix

Problem summary

  • This issue is caused by logic used to shrink the Java Heap when
    the workload is low in order to reduce the memory footprints
    caused by proactive expansion.
    

Problem conclusion

  • The shrink logic has been disabled by default.
    .
    This APAR will be fixed in the following Java Releases:
       6    SR16 FP60 (6.0.16.60)
       6 R1 SR8 FP60  (6.1.8.60)
       7    SR10 FP5  (7.0.10.5)
       7 R1 SR4 FP5   (7.1.4.5)
       8    SR4 FP5   (8.0.4.5)
    .
    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 number

    IV94294

  • Reported component name

    JAVA CLASS LIBS

  • Reported component ID

    620700130

  • Reported release

    700

  • Status

    CLOSED PER

  • PE

    NoPE

  • HIPER

    NoHIPER

  • Special Attention

    NoSpecatt / Xsystem

  • Submitted date

    2017-03-16

  • Closed date

    2017-04-10

  • Last modified date

    2018-08-22

  • 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

    JAVA CLASS LIBS

  • Fixed component ID

    620700130

Applicable component levels

  • R700 PSY

       UP

  • R800 PSY

       UP

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Document Information

Modified date:
21 February 2022