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PM56322: RDz: Memory Leak in Rational Developer for System z

A fix is available

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You can track all active APARs for this component.

 

APAR status

  • Closed as program error.

Error description

  • Java Out Of Memory Exception in Rational Developer for System z
    points to a problem with the MVS File System Miner.  In the Java
    Heap dumps one of the leak suspects was:
    
    One instance of
    'com.ibm.ftt.rse.mvs.server.miners.MVSFileSystemMiner'
    loaded by 'sun.misc.Launcher$AppClassLoader @ 0x234794e0'
    occupies
    108,502,656 (20.21%) bytes. The memory is accumulated in one
    instance of
    'java.util.HashMap$Entry[]' loaded by '<system class loader>'.
    
    In this case, the Java Out of Memory Exception occurred in:
    
    ---------------------------------------------------------------
    ERROR MVSDownloadHandler: java.lang.OutOfMemoryError
    java.lang.OutOfMemoryError
    at java.util.Arrays.copyOfRange(Arrays.java:4174)
    at java.util.Arrays.copyOf(Arrays.java:3893)
    at java.io.CharArrayWriter.write(CharArrayWriter.java:99)
    at
    com.ibm.ftt.rse.mvs.server.miners.MVSByteConverter.convert(MVSBy
    teConverter.java:155)
    at
    com.ibm.ftt.rse.mvs.server.miners.MVSByteConverter.convertSubBuf
    fer(MVSByteConverter.java:135)
    at
    com.ibm.ftt.rse.mvs.server.miners.MVSByteConverter.convertHostTo
    Client(MVSByteConverter.java:121)
    at
    com.ibm.ftt.rse.mvs.server.miners.MVSByteConverter.convertHostBy
    tesToClientBytes(MVSByteConverter.java:106)
    at
    com.ibm.ftt.rse.mvs.server.miners.MVSDownloadHandler.processBuff
    er(MVSDownloadHandler.java:276)
    at
    com.ibm.ftt.rse.mvs.server.miners.MVSFileSystemMiner.getFileAndA
    ttribute(MVSFileSystemMiner.java:2643)
    at
    com.ibm.ftt.rse.mvs.server.miners.MVSFileSystemMiner.getFileAndA
    ttribute(MVSFileSystemMiner.java:2727)
    at
    com.ibm.ftt.rse.mvs.server.miners.MVSFileSystemMiner.getFile(MVS
    FileSystemMiner.java:2587)
    at
    com.ibm.ftt.rse.mvs.server.miners.MVSDownloadHandler.handleDownl
    oad(MVSDownloadHandler.java:206)
    at
    com.ibm.ftt.rse.mvs.server.miners.MVSDownloadHandler.internalRun
    (MVSDownloadHandler.java:172)
    

Local fix

  • n/a
    

Problem summary

  • ****************************************************************
    * USERS AFFECTED: 01.All RDz users                             *
    *                 02.All RDz users                             *
    *                 03.All RDz users                             *
    *                 04.All RDz users                             *
    *                 05.All RDz users                             *
    ****************************************************************
    * PROBLEM DESCRIPTION: 01.OutOfMemory occurred owing to the    *
    *                         lack of Java heap.                   *
    *                      02.There is a case where the native     *
    *                         memory is damaged.                   *
    *                      03.OutOfmemory in Java heap occurred in *
    *                         RDz server                           *
    *                      04.RDz client may send command to       *
    *                         server even after the RDz client was *
    *                         canceled by RDz zOS command.         *
    *                      05.The protection exeption occurred in  *
    *                         readFile.                            *
    ****************************************************************
    * RECOMMENDATION:                                              *
    ****************************************************************
    01.OutofMemory condition occurred in RDz server process owing to
       the lack of Java heap.
    02.In the design, openConverter and closeConverter must not run
       at the same time. But there is a possibility that
       openConverter for for client A and closeConverter for client
       B run at the same time.
    03.OutOfmemory in Java heap occurred in RDz server
    04.RDz client may send command to server even after the RDz
       client was canceled by RDz zOS command.
    05.The protection exeption occurred in readFile when the dynamic
       allocation failed.
    

Problem conclusion

  • 01.MVSFileSystemMiner(Main in MVSminer) keeps the thread
       instances in the storage so that it could cancel the thread
       by the client. But the instances are never removed from the
       storage even after the thread is terminated.
       Now, the thread instances are removed from the storage when
       it finishes the process of the corresponding request.
    02.Now, openConverter and closeConverter will not run at the
       same time.
    03.Search action and Expand filter action invoke getDir method
       and MVS miner caches the result of getDir method. The growing
       of this cache causes OutOfMemory in JVM.
       Now, the caching mechanism is removed since the performance
       is not degraded without the cache.
    04.To protect MVS miners against unpredictable exceptions, MVS
       miner will reject the commands received after the RDz client
       was canceled.
    05.Now, RDz search process will skip the data set where the
       dynamic allocation failed.
    

Temporary fix

Comments

APAR Information

  • APAR number

    PM56322

  • Reported component name

    RD/Z HOST

  • Reported component ID

    5724T0723

  • Reported release

    760

  • Status

    CLOSED PER

  • PE

    NoPE

  • HIPER

    NoHIPER

  • Special Attention

    NoSpecatt

  • Submitted date

    2012-01-19

  • Closed date

    2012-08-23

  • Last modified date

    2012-08-28

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

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

Modules/Macros

  • FEKFMINE
    

Fix information

  • Fixed component name

    RD/Z HOST

  • Fixed component ID

    5724T0723

Applicable component levels

  • R760 PSY UK81273

       UP12/08/28 I 1000

Fix is available

  • Select the PTF appropriate for your component level. You will be required to sign in. Distribution on physical media is not available in all countries.

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Document Information

Modified date:
27 October 2020