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IV32836: HIGH CPU ISSUE CAUSED BY THE CONCURRENT GC HELPER THREAD

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You can track all active APARs for this component.

 

APAR status

  • Closed as program error.

Error description

  • Error Message: High CPU is reported some time after the
    concurrent garbage collection is started.
    .
    Stack Trace: This is a sample native stack trace:
    
     MM_ConcurrentCardTable::cleanCards
     MM_ConcurrentGC::conHelperEntryPoint
     con_helper_thread_proc2
     j9sig_protect
     con_helper_thread_proc
     thread_wrapper
    .
    

Local fix

  • This issue can be worked around using the
    -Xconcurrentbackground0.
    

Problem summary

  • The problem is caused when the concurrent background thread is
    spinning waiting for a data structure to be initialized.
    

Problem conclusion

  • This defect will be fixed in:
    6.0.1 SR5
    7.0.0 SR4
    .
    The JVM has been updated to prevent the concurrent background
    thread from spinning.
    

Temporary fix

Comments

APAR Information

  • APAR number

    IV32836

  • Reported component name

    J9 COMMON CODE

  • Reported component ID

    620700127

  • Reported release

    260

  • Status

    CLOSED PER

  • PE

    NoPE

  • HIPER

    NoHIPER

  • Special Attention

    NoSpecatt

  • Submitted date

    2012-11-30

  • Closed date

    2012-11-30

  • Last modified date

    2012-11-30

  • 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

    J9 COMMON CODE

  • Fixed component ID

    620700127

Applicable component levels

  • R260 PSY

       UP

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Document Information

Modified date:
21 February 2022