IBM Support

LI72426: SQL0973 SQLO_NOMEM_AGSH NO MEMORY AVAILABLE IN APPLICATION GROUP SHARED HEAP DUE TO EXCESSIVE FRAGMENTATION/MEMORY USAGE

Subscribe

You can track all active APARs for this component.

 

APAR status

  • Closed as fixed if next.

Error description

  • SQL0973 out of memory in Application Group Shared Heap error is
    returned.  This can occur when memory is exhausted in the
    Application Group Memory area.  It is due to a combination of
    fragmentation and excessive memory usage by the shared SQL
    Workspace.
    
    Only DPF (multi-partition), Intra-parallel, and Connnection
    Concentrator (MAX_CONNECTIONS > MAX_COORDAGENTS) environments
    are vulnerable.
    
    
    Sample db2diag.log entry:
    
    2007-04-24-11.07.40.759556-240 I7764319E517       LEVEL: Error
    PID     : 16984                TID  : 182968669984PROC : db2agen
    INSTANCE: db2inst1             NODE : 001         DB   : SAMPLE
    APPHDL  : 1-643                APPID: A1234567.F708.023084145709
    FUNCTION: DB2 UDB, access plan manager, sqlra_sqlW_copy_section,
    RETCODE : ZRC=0x8B0F0011=-1961951215=SQLO_NOMEM_AGSH
              "No memory available in 'Application Group Shared Heap
              DIA8300C A memory heap error has occurred.
    
    
    The db2pd command can be used to determine memory:
    
    1. memory set is exhausted (Commit is very close to Max)
       db2pd -db SAMPLE -memsets
    
       db2pd -memsets :
       Name         Used(Kb)   HWM(Kb)    Max(Kb)    Commit(Kb)
       AppCtl       218016     218592     220272     219840
    
    
    2. Application Group Shared Heap is fragmented, i.e. Physical
    Size (PhySz) is more than double Logical Size (LogSz)
    
       db2pd -db SAMPLE -mempools
    
       MemSet  PoolName  LogSz      LogUpBnd   PhySz      PhyUpBnd
       AppCtl  agsh      100351204  157859896  221462528  222986240
    

Local fix

  • A workaround for this APAR is to double the APPGROUP_MEM_SZ
    parameter value and reduce the GROUPHEAP_RATIO parameter by
    half, which reduces the size of the Application Group Shared
    Heap.
    

Problem summary

  • ****************************************************************
    *USERS AFFECTED:
    *          Systems using DPF (multi-partition), Concentrator
    *          (MAX_CONNECTIONS > MAX_COORDAGENTS),
    *          or intra-parallelism
    ****************************************************************
    *PROBLEM DESCRIPTION:
    *          SQL0973 out of Application Group Shared Heap may
    *          occur in rare workloads due to fragmentation of
    *          the Application Group Shared memory area.
    ****************************************************************
    *RECOMMENDATION:
    *          Upgrade to DB2 Version 9.1 fixpack 4 or higher.
    *          Use the links at the top of this APAR to
    *          download the latest fix packs for DB2 V9.1
    ****************************************************************
    

Problem conclusion

  • First Fixed in DB2 Version 9.1 fix pack 4
    

Temporary fix

  • double the APPGROUP_MEM_SZ parameter but decrease
     the GROUPHEAP_RATIO by half
    

Comments

  • DB2 Version 9.5 is not vulnerable to this problem.
    

APAR Information

  • APAR number

    LI72426

  • Reported component name

    DB2 UDE ESE LIN

  • Reported component ID

    5765F4104

  • Reported release

    910

  • Status

    CLOSED FIN

  • PE

    NoPE

  • HIPER

    NoHIPER

  • Special Attention

    NoSpecatt

  • Submitted date

    2007-05-28

  • Closed date

    2008-05-09

  • Last modified date

    2010-03-04

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

    LI72425

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

Modules/Macros

  • SQRA     SQO
    

Fix information

Applicable component levels

  • R910 PSY

       UP

[{"Business Unit":{"code":"BU058","label":"IBM Infrastructure w\/TPS"},"Product":{"code":"SSEPGG","label":"DB2 for Linux- UNIX and Windows"},"Platform":[{"code":"PF025","label":"Platform Independent"}],"Version":"910","Line of Business":{"code":"LOB10","label":"Data and AI"}}]

Document Information

Modified date:
07 January 2022