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IV25699: PERFORMACE REGRESSION OF HASHMAP/HASHTABLE/WEAKHASHMAP AFTER APPLYING APAR IV25852

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APAR status

  • Closed as program error.

Error description

  • Error Message: There is a performance regression when creating
    lots of HashMap/Hashtable/WeakHashMap new instances on all
    platforms.
    .
    Stack Trace: N/A
    .
    N/A
    

Local fix

  • Use previous JDK release which doesn't support alt hashing
    security fix.
    

Problem summary

  • There are 2 new object fields added to
    HashMap/Hashtable/WeakHashMap, one field will call some
    expensive method to initialize, even alt hashing is disabled.
    

Problem conclusion

  • This defect will be fixed in:
    6.0.0 SR12
    6.0.1 SR4
    7.0.0 SR3
    .
    The solution is to not call the expensive method when
    initializing the field if alt hashing is disabled.
    

Temporary fix

  • N/A
    

Comments

APAR Information

  • APAR number

    IV25699

  • 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

    2012-08-06

  • Closed date

    2012-08-30

  • Last modified date

    2012-11-02

  • APAR is sysrouted FROM one or more of the following:

  • APAR is sysrouted TO one or more of the following:

    IV27276

Fix information

  • Fixed component name

    JAVA CLASS LIBS

  • Fixed component ID

    620700130

Applicable component levels

  • R600 PSY

       UP

  • R700 PSY

       UP

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Document Information

Modified date:
02 November 2012