IC92518: INSTANCE MIGHT CRASH IF A QUERY THAT FEATURES A SORT IS RE-EXECUTED AFTER IT PREVIOUSY RECEIVED SQL0973.

Subscribe

You can track all active APARs for this component.

APAR status

  • Closed as program error.

Error description

  • An SQL might cause instance crash at sqlrifis2. An example stack
    trace might be like below:
    
    sqlrifis2
    sqlifnxt
    sqlirdk
    sqldIndexFetch
    sqldRowFetch
    
    This problem can happen if all the following conditions are met:
    a) SORT memory is low
    
    b) The query is run and it fails with sql0973 due to lack of
    sort memory.
       Users can see the out of memory error in the db2diag.log as
    below:
    
    2013-05-14-14.38.00.377730 I484339A914          LEVEL: Warning
    PID     : 7865             TID : 4394300991760  PROC : db2sysc
    INSTANCE: db2inst1         NODE : 000           DB   : SAMPLE
    APPHDL  : 0-11465          APPID: 192.168.1.1.2080.130514051704
    AUTHID  : DB2INST1         HOSTNAME: host01
    EDUID   : 713              EDUNAME: db2agent (SAMPLE)
    FUNCTION: DB2 UDB, SQO Memory Management,
    sqloCreateMemorySubPool, probe:130
    MESSAGE : ZRC=0x8B0F0012=-1961951214=SQLO_NOMEM_SHARED_SORT
              "No memory available in 'Shared Sort Heap'"
              DIA8300C A memory heap error has occurred.
    DATA #1 : String, 52 bytes
    Unable to allocate memory for the initial pool size.
    
    c) The same query is run again soon after (while it is still
    cached in the SQL workspace).
    
    The problem is most likely to be seen for a query with an access
    plan that contains a RIDSCAN over SORT.  The typical example
    here would be a plan that has something like this (example exfmt
    output):
    
          RIDSCN
          (  14)
          319827
             1
            |
          3000
          SORT
          (  15)
          319827
             1
            |
          3000
          IXSCAN
          (  16)
          10.0149
             1
    
    However, the problem is not limited to just plans like the
    above.  Any SORT that is "simple", like a RID sort as above, or
    a sort of just an integer column, has a chance to encounter the
    issue.
    

Local fix

  • Investigate the memory usage and configuration, and then take
    corrective tuning measures to avoid the memory limitations that
    lead to the problematic scenario.
    

Problem summary

  • ****************************************************************
    * USERS AFFECTED:                                              *
    * Users who run SQL involves simple sorts.                     *
    ****************************************************************
    * PROBLEM DESCRIPTION:                                         *
    * See Error Description                                        *
    ****************************************************************
    * RECOMMENDATION:                                              *
    * Please upgrade to V10.1 FixPack 3 or later.                  *
    ****************************************************************
    

Problem conclusion

  • This problem was first fixed in DB2 V10.1 FixPack 3.
    

Temporary fix

Comments

APAR Information

  • APAR number

    IC92518

  • Reported component name

    DB2 FOR LUW

  • Reported component ID

    DB2FORLUW

  • Reported release

    A10

  • Status

    CLOSED PER

  • PE

    NoPE

  • HIPER

    NoHIPER

  • Special Attention

    NoSpecatt

  • Submitted date

    2013-05-23

  • Closed date

    2013-10-07

  • Last modified date

    2013-10-07

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

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

    IC95357 IC95479

Fix information

  • Fixed component name

    DB2 FOR LUW

  • Fixed component ID

    DB2FORLUW

Applicable component levels

  • RA10 PSN

       UP



Rate this page:

(0 users)Average rating

Add comments

Document information


More support for:

DB2 for Linux, UNIX and Windows

Software version:

10.1

Reference #:

IC92518

Modified date:

2013-10-07

Translate my page

Machine Translation

Content navigation