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IV29816: Virtual machine unnecessarily serializes class loading when class loader is parallel capable

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You can track all active APARs for this component.

APAR status

  • Closed as program error.

Error description

  • Error Message: N/A
    .
    Stack Trace: N/A
    

Local fix

  • N/A
    

Problem summary

  • The Java virtual machine (VM) serializes multiple threads'
    concurrent attempts to load the same class using the same class
    loader.
    This prevents linkage errors from multiple attempts to define
    the class.
    Java 7 allows class loaders to manage concurrent class loading
    themselves if they register as parallel capable. This may be
    incompatible with the VM's
    serialization.
    

Problem conclusion

  • This defect will be fixed in:
    7.0.0 SR4
    6.0.1 SR5
    .
    If the classloader is registered as parallel-capable, the VM
    disables serialization of concurrent class loading using that
    class loader.
    

Temporary fix

Comments

APAR Information

  • APAR number

    IV29816

  • 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

    2012-10-09

  • Closed date

    2012-11-23

  • Last modified date

    2012-11-23

  • 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



Document information

More support for: Runtimes for Java Technology
Virtual Machine

Software version: 260

Reference #: IV29816

Modified date: 23 November 2012