IV19697: APPLICATION HANG WITH HIGH CPU UTILIZATION

Subscribe to this APAR

By subscribing, you receive periodic emails alerting you to the status of the APAR, along with a link to the fix after it becomes available. You can track this item individually or track all items by product.

Notify me when this APAR changes.

Notify me when an APAR for this component changes.

APAR status

  • Closed as program error.

Error description

  • Error Message: The Java application stops making progress while
    still using CPU resources (livelock)
    .
    Stack Trace: The native stack trace will most likely contain
    functions related to allocation and freeing of optimization
    plans used by the JIT
    .
    

Local fix

Problem summary

  • This rare problem needs all of the following conditions to
    occur:
    (1) Two compilation requests for the same method occur in
    parallel.
    (2) GC has requested all threads to stop because it wants to
    proceed exclusively
    (3) The application uses Compiler.disable() interface to disable
    JIT operation
    (4) The requested compilation is a synchronous one which is a
    rare event in itself
    These conditions can lead to a situation where one compilation
    request has just started, but stopped because of the GC request.
    The GC is blocked because of another Java thread not yielding.
    The other Java thread continuously tries to compile the same
    method, but cannot because JIT is disabled (due to
    Compiler.disable call) and at the same time cannot abort the
    compilation because another attempt is already in progress
    

Problem conclusion

  • This defect will be fixed in:
    6.0.1 SR2
    7.0.0 SR1
    .
    The situation described in the "Problem Summary" has been
    addressed by forcing the second Java thread to yield to GC and
    wait for the compilation result (despite the Compiler.disable
    directive). This allows GC to continue which then unblocks the
    compilation thread which unblocks the two Java threads waiting
    for the compilation result
    

Temporary fix

Comments

APAR Information

  • APAR number

    IV19697

  • Reported component name

    JIT

  • Reported component ID

    620700124

  • Reported release

    260

  • Status

    CLOSED PER

  • PE

    NoPE

  • HIPER

    NoHIPER

  • Special Attention

    NoSpecatt

  • Submitted date

    2012-04-13

  • Closed date

    2012-04-13

  • Last modified date

    2012-04-13

  • 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

  • R260 PSY

       UP



Rate this page:

(0 users)Average rating

Add comments

Document information


More support for:

Runtimes for Java Technology
Just In Time (JIT) Compiler

Software version:

260

Reference #:

IV19697

Modified date:

2012-04-13

Translate my page

Machine Translation

Content navigation