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IC66254: WHEN A GPFS CONTAINING THE INSTANCE DIRECTORY (SQLLIB) IS LOST O NA SYSTEM, IT RESULTS IN HIGH CPU USAGE BY DB2SYSC

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You can track all active APARs for this component.

APAR status

  • Closed as program error.

Error description

  • When a GPFS filesystem containing the instance directory
    (sqllib, where DB2 binaries and libraries reside) is lost on a
    system, both db2sysc and db2fmp processes go into a defunct
    state and start consuming high CPU, the result of which is due
    to the process being stuck in infinite recursion with a signal
    handler. Even a kill with a signal 9 against these defunct DB2
    processes would not cleanup.
    
    Callstack for db2sysc via a debugger would show the following
    stack recursively:
    #0  0x00002adf7d8fa634 in do_lookup_x ()
    from /lib64/ld-linux-x86-64.so.2
    
    #1  0x00002adf7d8faa87 in _dl_lookup_symbol_x ()
       from /lib64/ld-linux-x86-64.so.2
    #2  0x00002adf7d8fe0b5 in _dl_fixup ()
      from /lib64/ld-linux-x86-64.so.2
    
    #3  0x00002adf7d9034d2 in _dl_runtime_resolve ()
       from /lib64/ld-linux-x86-64.so.2
    #4  0x00002adf7ef45d04 in pdlogNestedTrapHandler ()
       from /opt/tivoli/tsm/db2/lib64/libdb2e.so.1
    #5  <signal handler called>
    #6  0x00002adf7d8fa634 in do_lookup_x ()
       from /lib64/ld-linux-x86-64.so.2
    
    #7  0x00002adf7d8faa87 in _dl_lookup_symbol_x ()
       from /lib64/ld-linux-x86-64.so.2
    #8  0x00002adf7d8fe0b5 in _dl_fixup () from
    /lib64/ld-linux-x86-64.so.2
    #9  0x00002adf7d9034d2 in _dl_runtime_resolve ()
       from /lib64/ld-linux-x86-64.so.2
    #10 0x00002adf7ef45d04 in pdlogNestedTrapHandler ()
       from /opt/tivoli/tsm/db2/lib64/libdb2e.so.1
    #11 <signal handler called>
    

Local fix

  • To workaround, either reboot the system or kill db2wdog process
    with a signal 9 (this will clean up defunct DB2 processes).
    

Problem summary

  • ****************************************************************
    * USERS AFFECTED:                                              *
    * ALL                                                          *
    ****************************************************************
    * PROBLEM DESCRIPTION:                                         *
    * WHEN A GPFS CONTAINING THE INSTANCE DIRECTORY (SQLLIB) IS    *
    * LOST ON A SYSTEM, IT RESULTS IN HIGH CPU USAGE BY DB2SYSC    *
    ****************************************************************
    * RECOMMENDATION:                                              *
    * Upgrade to 9.7 FP2                                           *
    ****************************************************************
    

Problem conclusion

  • WHEN A GPFS CONTAINING THE INSTANCE DIRECTORY (SQLLIB) IS LOST
    ON A SYSTEM, IT RESULTS IN HIGH CPU USAGE BY DB2SYSC
    

Temporary fix

Comments

APAR Information

  • APAR number

    IC66254

  • 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

    2010-02-11

  • Closed date

    2010-09-13

  • Last modified date

    2010-09-13

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

    IC64748

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

    IC67180

Fix information

  • Fixed component name

    DB2 FOR LUW

  • Fixed component ID

    DB2FORLUW

Applicable component levels

  • R970 PSN

       UP



Document information

More support for: DB2 for Linux, UNIX and Windows

Software version: 9.7

Reference #: IC66254

Modified date: 13 September 2010