IBM Support

IV74925: PERFORMANCE DEGRADATION WITH JDK 1.6 IMPLEMENTATION OF JAVA.UTI L.CONCURRENT.ATOMIC.ATOMICLONG CLASS

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APAR status

  • Closed as program error.

Error description

  • Error Message: N/A
    .
    Stack Trace: 3XMTHREADINFO3 Java callstack:4XESTACKTRACE
    
    at
    java/util/concurrent/atomic/AtomicLong.incrementAndGet(AtomicLon
    g.java:205(Compiled Code))
    .
    Other methods of AtomicLong also show a similar performance
    degradation with JDK 1.6 implementation
    

Local fix

  • NA
    

Problem summary

  • IBM JDK 6  implemented a Java level synchronization to work
    around an operating system level cache lock performance
    bottleneck. As the operating system cache performance bottleneck
    is resolved over period of time, it overtakes the Java level
    synchronization performance  and hence the current performance
    degradation is observed compared to the reference
    implementation.
    

Problem conclusion

  • IBM JDK has been updated to remove the work around using  Java
    level synchronization  as the operating system level cache
    performance bottleneck no more exists. Now the implementation is
    same as reference implementation in JDK 7.
    .
    This APAR will be fixed in the following Java Releases:
       6    SR16 FP7  (6.0.16.7)
       6 R1 SR8 FP7   (6.1.8.7)
    .
    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

    IV74925

  • Reported component name

    JAVA CLASS LIBS

  • Reported component ID

    620700130

  • Reported release

    600

  • Status

    CLOSED PER

  • PE

    NoPE

  • HIPER

    NoHIPER

  • Special Attention

    NoSpecatt

  • Submitted date

    2015-07-08

  • Closed date

    2015-07-08

  • Last modified date

    2015-07-08

  • 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

  • R600 PSY

       UP

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Document Information

Modified date:
08 July 2015