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JR35057: REPLICATION ENGINE FIXES FOR DB2 LUW V9.1 FP9

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You can track all active APARs for this component.

 

APAR status

  • Closed as program error.

Error description

  • V91FP9 Repl Engine Fixes
    

Local fix

  • V91FP9 Repl Engine Fixes
    

Problem summary

  • The following problem has been fixed in DB2 LUW V9.1 FP9:
    Defect: wsdbu00614335: SQLCAPTURE can miss rows when a
    transaction already published by the worker thread is
    spilled by the log reader thread because memory limit is
    reached
    .
    User Affected: SQLCAPTURE and QCAPTURE
    .
    Problem Description: Replication users might experience
    data loss when the Capture program spills a transaction
    that is smaller than the memory limit and the commit
    interval is reached.
    .
    Problem Summary: In asynchronous log reading mode, which
    is the default for the QCAPTURE program and enabled by
    setting the invocation parameter ASYNCHLOGRD to Y for
    the SQLCAPTURE program, a dedicated log reader thread
    reads the log records and spills transactions to disk
    when MEMORY_LIMIT is about to be exceeded.  A memory
    corruption can occur within a small timing window where
    a transaction already published by the worker thread is
    selected for spilling by the log reader thread and the
    commit_interval is reached during this spilling.  This
    problem does not exist if the transaction is the only
    one being captured, such as when a single transaction
    is larger than the memory limit for the Capture program.
    As a result, the spilled transaction or parts of the
    spilled transaction might not get published.  This
    problem can actually also cause data loss or duplicate
    rows in transactions that follow the spilled transaction.
    .
    Problem Conclusion: The Capture logic has been fixed to
    prevent a transaction already published by the worker
    thread from being selected for spilling.
    

Problem conclusion

  • The problem described has been fixed in
    DB2 LUW V9.1 FP9.
    

Temporary fix

Comments

APAR Information

  • APAR number

    JR35057

  • Reported component name

    WS Q-REPLIC LUW

  • Reported component ID

    5724N9801

  • Reported release

    910

  • Status

    CLOSED PER

  • PE

    NoPE

  • HIPER

    NoHIPER

  • Special Attention

    NoSpecatt

  • Submitted date

    2009-12-07

  • Closed date

    2010-04-08

  • Last modified date

    2010-04-08

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

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

    JR35624

Fix information

  • Fixed component name

    WS Q-REPLIC LUW

  • Fixed component ID

    5724N9801

Applicable component levels

  • R910 PSY

       UP

[{"Business Unit":{"code":"BU059","label":"IBM Software w\/o TPS"},"Product":{"code":"SSDP5R","label":"InfoSphere Replication Server"},"Platform":[{"code":"PF025","label":"Platform Independent"}],"Version":"9.1","Line of Business":{"code":"LOB10","label":"Data and AI"}}]

Document Information

Modified date:
12 October 2021