IBM Support

IT07938: MANY INVALID LINKS IN DEDUP POOL CAUSES SLOW RESTORE STGPOOL PERFORMANCE

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APAR status

  • Closed as program error.

Error description

  • When there are invalidated dedup links in a deduplicated storage
    pool, RESTORE STGPOOL can be used to re-link or restore some of
     those links. If there are many invalidated links, the restore
    stgpool process can take a long time without any apparent
    progress. The more invalidated links there are, the longer the
    process will take.
    
    Tivoli Storage Manager Versions Affected:
    Tivoli Storage Manager server version V6 and V7
    
    Customer/L2 Diagnostics (If Applicable)
    Collect servermonV6.pl data for analysis. The SHOW THREADS
    output for the restore thread will show this call stack:
    0000000076FB12FA NtWaitForSingleObject()+a
    000007FEFD0610DC WaitForSingleObjectEx()+9c
    000007FEF929C640 sqloWaitInterrupt()+280
    000007FEF9214137 sqloSSemP()+47
    000007FEF7725024 sqlccIPCWaitForReceive()+3264
    000007FEF772A6C5 sqlccrecv()+195
    000007FEF78D2D19 sqljcReadGetPtrInt()+2899
    000007FEF78EFB55 sqljrDrdaArOpen()+175
    000007FEF7959325 csmCursorBlaster()+1d35
    000007FEF7C0927A CLI_CheckLicense()+991a
    000007FEF7A9D339 SQLExecute()+2999
    000007FEF7A9ACED SQLExecute()+34d
    000007FEE3AAB4A6 tbRegExecEx()+466
    000007FEE35F9928 BfRestoreInvalidLinks()+318
    000007FEE36BF5D5 AfRestorePoolThread()+325
    000007FEE34172EC startThread()+13c
    000007FEF8DF3D67 beginthreadex()+107
    000007FEF8DF3F0E endthreadex()+192
    0000000076E559ED BaseThreadInitThunk()+d
    0000000076F8C541 RtlUserThreadStart()+21
    
    The call stack shows it is waiting for a DB2 SQL execution.
    Review the db2.txt output to see which SQL is causing the delay.
    An output similar to the following indicates a performance issue
    (Note the ELAPSED_TIME_SEC is very high):
    COMMAND: db2 "select elapsed_time_sec,
    substr(activity_state,1,4) as state, substr( stmt_text, 1, 512)
    as stmt_text from sysibmadm.mon_current_sql where
    elapsed_time_sec > 1"
    
     ELAPSED_TIME_SEC STATE STMT_TEXT
     ---------------- ----- ---------
                49807 EXEC  SELECT DISTINCT be2.bfid, be2.superbfid,
    be2.poolid, be2.digest_type, be2.digest_value, bf.offset,
    bf.length, afsg.volid, afsg.start FROM TSMDB1.bf_bitfile_extents
    AS be1, TSMDB1.bf_bitfile_extents AS be2 LEFT JOIN
    TSMDB1.bf_aggregated_bitfiles AS bf ON ( bf.bfid=be2.bfid AND
    bf.superbfid=be2.superbfid  AND bf.srvid=be2.srvid AND
    bf.length>0 ) LEFT JOIN TSMDB1.af_segments AS afsg ON
    (afsg.poolid=be2.poolid AND afsg.bfid=be2.superbfid  AND
    afsg.srvid=be2.srvid ) LEFT JOIN TSMDB1.af_damaged AS afda ON
    (afda.p
    
    Initial Impact:
    Low
    
    Additional Keywords:
    TSM slow damaged dedupaudit
    

Local fix

  • Wait for restore stgpool to complete.
    

Problem summary

  • ****************************************************************
    * USERS AFFECTED:                                              *
    * All Tivoli Storage Manager server users.                     *
    ****************************************************************
    * PROBLEM DESCRIPTION:                                         *
    * See ERROR DESCRIPTION.                                       *
    ****************************************************************
    * RECOMMENDATION:                                              *
    * Apply fixing level when available. This problem is currently *
    * projected to be fixed in level 7.1.3. Note that this is      *
    * subject to change at the discretion of IBM.                  *
    ****************************************************************
    

Problem conclusion

  • This problem was fixed.
    Affected platforms:  AIX, HP-UX, Solaris, Linux, and Windows.
    

Temporary fix

Comments

APAR Information

  • APAR number

    IT07938

  • Reported component name

    TSM SERVER

  • Reported component ID

    5698ISMSV

  • Reported release

    71W

  • Status

    CLOSED PER

  • PE

    NoPE

  • HIPER

    NoHIPER

  • Special Attention

    NoSpecatt

  • Submitted date

    2015-03-26

  • Closed date

    2015-05-08

  • Last modified date

    2015-05-08

  • 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

    TSM SERVER

  • Fixed component ID

    5698ISMSV

Applicable component levels

  • R71A PSY

       UP

  • R71H PSY

       UP

  • R71L PSY

       UP

  • R71S PSY

       UP

  • R71W PSY

       UP



Document information

More support for: Tivoli Storage Manager

Software version: 71W

Reference #: IT07938

Modified date: 08 May 2015