IBM Support

IT17044: MFT agent generates an FFDC file reporting a concurrent modification exception

Subscribe

You can track all active APARs for this component.

 

APAR status

  • Closed as program error.

Error description

  • If a java.lang.OutOfMemory exception occurs within a WebSphere
    MQ Managed File Transfer agent, then a
    java.util.ConcurrentModificationException can occur.
    An FFDC file is generated by the agent containing the following
    information:
    
    Level:      f750-FP-006-20160219-0939
    Time:       09/06/2016 12:45:19:352 CEST
    Thread:     28 (ReplyProcessor)
    Class:      com.ibm.wmqfte.thread.FTEThread
    Method:     uncaughtException
    Probe:      FFDC_001
    Cause:      java.util.ConcurrentModificationException
    java.util.ConcurrentModificationException
     at
    java.util.HashMap$AbstractMapIterator.checkConcurrentMod(HashMap
    .java:197)
     at
    java.util.HashMap$AbstractMapIterator.remove(HashMap.java:221)
     at
    com.ibm.wmqfte.wmqiface.WMQApiImpl.disconnectWMQConnections(WMQA
    piImpl.java:140)
     at
    com.ibm.wmqfte.thread.FTEThread.uncaughtException(FTEThread.java
    :91)
     at java.lang.Thread.uncaughtException(Thread.java:1249)
    

Local fix

Problem summary

  • ****************************************************************
    USERS AFFECTED:
    This issue affects all users of MQ Managed File Transfer.
    
    
    Platforms affected:
    MultiPlatform
    
    ****************************************************************
    PROBLEM DESCRIPTION:
    After an unexpected error condition occurs within an MQ Managed
    File Transfer (MFT) agent process, such as a
    java.lang.OutOfMemory exception, before the agent JVM terminates
    an FFDC reporting a java.util.ConcurrentModificationException is
    generated.  This occurred when the thread that experienced the
    unexpected error condition attempted to disconnect and destroy
    any connections to the MQ agent queue manager that were
    previously created by that thread.
    
    This APAR, which is similar to APAR IT05252, fixes another
    condition where a data structure containing connections to a
    queue manager (otherwise known as hConns) could have been
    modified while a thread is iterating over it.
    

Problem conclusion

  • The MQ Managed File Transfer product code has been updated to
    remove the condition where a
    java.util.ConcurrentModificationException can occur while a
    thread, which has experienced an unexpected error condition, is
    disconnecting connections to a queue manager.
    
    ---------------------------------------------------------------
    The fix is targeted for delivery in the following PTFs:
    
    Version    Maintenance Level
    v7.5       7.5.0.8
    v8.0       8.0.0.6
    v9.0 CD    9.0.2
    v9.0 LTS   9.0.0.1
    
    The latest available FTE maintenance can be obtained from
    'Fix List for WebSphere MQ File Transfer Edition 7.0'
    http://www-01.ibm.com/support/docview.wss?uid=swg27015313
    
    The latest available MQ maintenance can be obtained from
    'WebSphere MQ Recommended Fixes'
    http://www-1.ibm.com/support/docview.wss?rs=171&uid=swg27006037
    
    If the maintenance level is not yet available information on
    its planned availability can be found in 'WebSphere MQ
    Planned Maintenance Release Dates'
    http://www-1.ibm.com/support/docview.wss?rs=171&uid=swg27006309
    ---------------------------------------------------------------
    

Temporary fix

Comments

APAR Information

  • APAR number

    IT17044

  • Reported component name

    WMQ MFT

  • Reported component ID

    5724H7242

  • Reported release

    750

  • Status

    CLOSED PER

  • PE

    NoPE

  • HIPER

    NoHIPER

  • Special Attention

    NoSpecatt / Xsystem

  • Submitted date

    2016-09-23

  • Closed date

    2016-10-28

  • Last modified date

    2017-06-01

  • 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

    WMQ MFT

  • Fixed component ID

    5724H7242

Applicable component levels

  • R750 PSY

       UP

[{"Business Unit":{"code":"BU053","label":"Cloud & Data Platform"},"Product":{"code":"SSCUHLE","label":"WMQ Managed File Transfer"},"Component":"","ARM Category":[],"Platform":[{"code":"PF025","label":"Platform Independent"}],"Version":"7.5","Edition":"","Line of Business":{"code":"","label":""}}]

Document Information

Modified date:
01 June 2017