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IC67425: DB2 ABENDS USING SCALAR AGGREGATION FUNCTION WITH CONNECTION CONCENTRATOR ENABLED

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You can track all active APARs for this component.

 

APAR status

  • Closed as program error.

Error description

  • PROBLEM DESCRIPTION:
    ====================
    When using Scalar Aggregation functions with Connection
    Concentrator enabled, memory allocated for the scalar
    aggregation execution may become invalid when the connection is
    serviced by different agents, causing DB2 to trap/abend.  An
    additional requirement is that "with hold cursors" are being
    used, but this is common.
    
    Connection Concentrator is enabled when the database manager
    configuration parameter MAX_CONNECTIONS exceeds MAX_COORDAGENTS.
    This criteria applies when these parameters are set to
    AUTOMATIC, in which case the criteria applies to the underlying
    values.
    For example, this configuration shows Connection Concentrator
    enabled:
     Max number of coordinating agents     (MAX_COORDAGENTS) =
    AUTOMATIC(200)
     Max number of client connections      (MAX_CONNECTIONS) =
    AUTOMATIC(1000)
    
    Example diagnostic trap files will include the keyword/function
    sqlriScalagClose:
    
    Example 1:
    <StackTrace>
    ...
    sqloEDUCodeTrapHandler + 0x0107
    address: 0x00002AAAAABD4C00
    sqldmcloP8sqeAgentPP8SQLD_CCBi + 0x002a
    sqlriScalagCloseDropTempP8sqlrr_cbP16sqlri_buffer_mgr + 0x007f
    sqlri_buffer_closeP8sqlrr_cbP15sqlri_scalagobj + 0x021d
    sqlriScalagCloseP8sqlrr_cbP15sqlri_scalagobj + 0x003c
    
    Example 2:
    <StackTrace>
    ...
    sqloCrashOnCriticalMemoryValidationFailure + 0x1C
    diagnoseMemoryCorruptionAndCrash__13SQLO_MEM_POOLFUlCPCc + 0x260
    sqloDiagnoseFreeBlockFailure__FP8SMemFBlk + 0x748
    sqloDiagnoseFreeBlockFailure__FP8SMemFBlk@glue69E + 0x74
    sqlofmblkEx + 0x48
    sqlri_buffer_close__FP8sqlrr_cbP15sqlri_scalagobj + 0xB0
    sqlriScalagClose__FP8sqlrr_cbP15sqlri_scalagobj + 0x2C
    sqlriScalagClose__FP8sqlrr_cbP15sqlri_scalagobj@glue10D1 + 0x70
    sqlricjpInfrequent__FP8sqlrr_cbPP12sqlri_opparml + 0x4
    sqlricjp__FP8sqlrr_cbP12sqlri_opparmilT4 - 0x170
    sqlricls_simple__FP8sqlrr_cbil + 0xCC
    

Local fix

  • Disable Connection Concentrator:
    db2 update dbm cfg using MAX_CONNECTIONS -1 automatic
    db2stop;db2start
    
    This results in the following standard configuration:
     Max number of coordinating agents     (MAX_COORDAGENTS) =
    AUTOMATIC(200)
     Max number of client connections      (MAX_CONNECTIONS) =
    AUTOMATIC(MAX_COORDAGENTS)
    

Problem summary

  • ****************************************************************
    * USERS AFFECTED:                                              *
    * Systems with Connection Concentrator enabled                 *
    * (MAX_CONNECTIONS > MAX_COORDAGENTS)                          *
    ****************************************************************
    * PROBLEM DESCRIPTION:                                         *
    * See Error Description                                        *
    ****************************************************************
    * RECOMMENDATION:                                              *
    * Upgrade to Fix Pack 3a or disable Connection Concentrator    *
    ****************************************************************
    

Problem conclusion

  • Problem first fixed in DB2 Version 9.7 Fix Pack 3a build s101006
    

Temporary fix

Comments

APAR Information

  • APAR number

    IC67425

  • Reported component name

    DB2 FOR LUW

  • Reported component ID

    DB2FORLUW

  • Reported release

    970

  • Status

    CLOSED PER

  • PE

    NoPE

  • HIPER

    NoHIPER

  • Special Attention

    NoSpecatt

  • Submitted date

    2010-03-24

  • Closed date

    2010-11-02

  • Last modified date

    2010-11-02

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

    IC67420

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

Fix information

  • Fixed component name

    DB2 FOR LUW

  • Fixed component ID

    DB2FORLUW

Applicable component levels

  • R970 PSN

       UP

[{"Business Unit":{"code":"BU048","label":"IBM Software"},"Product":{"code":"SSEPGG","label":"DB2 for Linux, UNIX and Windows"},"Component":"","ARM Category":[],"Platform":[{"code":"PF025","label":"Platform Independent"}],"Version":"9.7","Edition":"","Line of Business":{"code":"LOB10","label":"Data and AI"}}]

Document Information

Modified date:
02 November 2010