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IV56526: HIGH CPU HANG IN JIT COMPILED METHOD

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You can track all active APARs for this component.

APAR status

  • Closed as program error.

Error description

  • Error Message: An otherwise correctly operating application
    hangs with high (single) cpu load. Analysis shows the looping
    method has been compiled by the JIT.
    .
    Stack Trace: N/A
    .
    

Local fix

  • The problem can be avoided by disabling the redundant async
    check optimization with the following JIT
    option:-Xjit:disableRedundantAsyncCheckRemoval
    

Problem summary

  • In certain rare circumstances the redundant async check removes
    an async check that is required for correct option. The purpose
    of the async check is to ensure that a looping java thread can
    be interrupted when necessary, for example when a global GC
    needs to be performed. The missing async check can therefore
    result in a busy hang with one thread looping while all the
    remaining threads are waiting for some global event.
    

Problem conclusion

  • This APAR will be fixed in the following Java Releases:
       6    SR16      (6.0.16.0)
       7    SR7       (7.0.7.0)
       7 R1 SR1       (7.1.1.0)
    .
    The JIT has been modified to make sure that the necessary async
    checks are not removed.
    

Temporary fix

Comments

APAR Information

  • APAR number

    IV56526

  • Reported component name

    JIT

  • Reported component ID

    620700124

  • Reported release

    600

  • Status

    CLOSED PER

  • PE

    NoPE

  • HIPER

    NoHIPER

  • Special Attention

    NoSpecatt

  • Submitted date

    2014-03-10

  • Closed date

    2014-04-07

  • Last modified date

    2014-04-29

  • 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

  • R600 PSY

       UP

  • R260 PSY

       UP

  • R130 PSY

       UP



Document information

More support for: Runtimes for Java Technology
Just In Time (JIT) Compiler

Software version: 6.0

Reference #: IV56526

Modified date: 29 April 2014