IBM Support

PM17689: LockTimeoutException in replica shard

Subscribe

You can track all active APARs for this component.

 

APAR status

  • Closed as program error.

Error description

  • When using transaction isolation with PESSIMISTIC LockStrategy
    to avoid deadlocks on the primary shard, LockTimeoutException
    due to deadlocks can be seen when using synchronous replication.
    

Local fix

Problem summary

  • ****************************************************************
    * USERS AFFECTED:  All users of WebSphere eXtreme Scale who    *
    *                  use Read Committed or Read Uncomitted       *
    *                  transaction isolation level with            *
    *                  replication enabled.                        *
    ****************************************************************
    * PROBLEM DESCRIPTION: A LockTimeoutException exception        *
    *                      occurs on a synchronous replica shard.  *
    ****************************************************************
    * RECOMMENDATION:                                              *
    ****************************************************************
    When a Read committed or Read uncommitted isolation level is
    used with pessimistic locking on a primary shard, deadlocks are
    avoided when fetches are performed in mixed order. With
    replication, the runtime uses Repeatable reads on the
    replica, which results in deadlocks. The runtime code was
    modified so that locks are no longer otained for
    fetch operations on a replica shard.
    

Problem conclusion

  • A future cumulative fix will correct the problem.
    

Temporary fix

Comments

APAR Information

  • APAR number

    PM17689

  • Reported component name

    XD VIRTUAL ENTE

  • Reported component ID

    5724J3403

  • Reported release

    700

  • Status

    CLOSED PER

  • PE

    NoPE

  • HIPER

    NoHIPER

  • Special Attention

    NoSpecatt

  • Submitted date

    2010-07-01

  • Closed date

    2010-08-05

  • Last modified date

    2010-08-05

  • 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

    XD EXTREME SCAL

  • Fixed component ID

    5724J3402

Applicable component levels

  • R610 PSY

       UP

  • R700 PSY

       UP

  • R710 PSY

       UP

[{"Business Unit":{"code":"BU053","label":"Cloud & Data Platform"},"Product":{"code":"SSTVLU","label":"WebSphere eXtreme Scale"},"Component":"","ARM Category":[],"Platform":[{"code":"PF025","label":"Platform Independent"}],"Version":"7.0","Edition":"","Line of Business":{"code":"LOB45","label":"Automation"}}]

Document Information

Modified date:
23 September 2020