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IT20648: IT15176 FIX COMPLETION: "GENERATE BACKUPSET" MIGHT LOOK HUNG FORVERY LARGE FILESYSTEMS

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You can track all active APARs for this component.

APAR status

  • Closed as program error.

Error description

  • IBM Spectrum Protect GENERATE BACKUPSET command might be slow
    for huge node/filespace, even with the fix for IT15176 applied.
    
    To verify you are affected to the APAR, collect the following
    docs as DB2 instance user:
    
    Change to the db2/misc directory, on a Linux system that is:
    cd   /opt/tivoli/tsm/db2/misc
    
    db2 connect to tsmdb1
    db2 -tvf EXPLAIN.DDL
    db2 set current explain mode explain
    
    db2 "Select imbk.nodeid, imbk.fsid, imbk.objtype, imbk.hl_name,
    imbk.ll_name, imbk.state, imbk.insdate, imbk.objid,
    imbk.deacdate, imbk.objinfo, imbk.owner, imbk.mcid, imbk.cgid,
    cast(null as varchar(1)) as encrypt_key, cast(null as bigint) as
    bfsize, cast(null as smallint) as hdrsize, cast(null as bigint)
    as sharedobjid, cast(null as smallint) as send_hdr, cast(null as
    smallint) as stg_hint, cast(null as integer) as attrlength,
    imbk.extobjid,  imbk.exttoken, imbk.grouptype, imbk.groupid,
    cast(null as varchar(1)) as recogtoken,imbk.tocentries,
    imbk.bypassrecog, imbk.metadatasize, imbk.flags FROM
    tsmdb1.Backupset_BACKOBJS BSBK, tsmdb1.BACKUP_OBJECTS IMBK where
    not exists (select bkset_objid from
    tsmdb1.Backupset_Temp_Objects toc where
    BSBK.BSBK_OBJID=TOC.BKSET_OBJID and TOC.BKSET_DATATYPE=?) and
    BSBK.BSBK_PROCID=? and BSBK.bsbk_objid>? and
    BSBK.BSBK_OBJID=IMBK.OBJID order by BSBK.bsbk_objid fetch first
    40000 rows only optimize for 40000 rows FOR READ ONLY WITH UR"
    
    db2exfmt -d tsmdb1 -1 -o explainoutput.txt
    
    Have a look and verify if DB2 in the access plan decides to use
    a hash join (HSJOIN) for the BACKUP_OBJECTS table as in the
    following explainoutput.txt extract:
    
                            ...
                             |
                          0,537384
                           ^HSJOIN
                           (   5)
                           7272,46
                           2640,62
                   /---------+---------\
               31314,1                 5325,22
               FETCH                   IXSCAN
               (   6)                  (  10)
               7209,08                 62,2807
               2625,31                 15,3164
             /---+----\                  |
         31314,1    3,10308e+08      8,46802e+06
         RIDSCN   TABLE: TSMDB1    INDEX: TSMDB1
         (   7)   BACKUP_OBJECTS      BSBK_NDX
         248,229        Q2               Q3
         30,8883
           |
         31314,1
         SORT
         (   8)
         248,229
         30,8883
           |
         31314,1
         IXSCAN
         (   9)
         240,989
         30,8883
           |
       3,10308e+08
     INDEX: TSMDB1
        IMBK_NDX
           Q2
    
    
      IBM Spectrum Protect Versions Affected: all supported
      Initial Impact: Medium
      Additional Keywords: NLJOIN HSJOIN OPTGUIDELINES TSM hang
    performance
      | MDVPARTL 8.1.1.0-TIV_5698ISMSV |
    

Local fix

Problem summary

  • ****************************************************************
    * USERS AFFECTED:                                              *
    * All IBM Spectrum Protect server users.                       *
    ****************************************************************
    * PROBLEM DESCRIPTION:                                         *
    * See ERROR DESCRIPTION.                                       *
    ****************************************************************
    * RECOMMENDATION:                                              *
    * Apply fixing level when available.This problem is currently  *
    * projected to be fixed in levels 7.1.8 and 8.1.2. 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

    IT20648

  • Reported component name

    TSM SERVER

  • Reported component ID

    5698ISMSV

  • Reported release

    71L

  • Status

    CLOSED PER

  • PE

    NoPE

  • HIPER

    NoHIPER

  • Special Attention

    NoSpecatt / Xsystem

  • Submitted date

    2017-05-18

  • Closed date

    2017-05-25

  • Last modified date

    2017-05-25

  • 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

  • R71L PSY

       UP

  • R71S PSY

       UP

  • R71W PSY

       UP

  • R71H PSY

       UP



Document information

More support for: Tivoli Storage Manager

Software version: 7.1.3

Reference #: IT20648

Modified date: 25 May 2017