IT27666: DB2 INSTANCE PANIC WHILE RUNNING QUERIES INVOLVING A SORT OPERATOR

APAR status

• Closed as program error.

Error description

• When running a query involving one or more SORT operators, the
  instance may trap with the following sequence of entries in
  db2diag.log:
  
  2018-12-14-19.54.19.930024+060 I20820212E4728        LEVEL:
  Severe
  PID     : 59071                TID : 140251481761536 PROC :
  db2sysc 0
  INSTANCE: db2inst1             NODE : 000            DB   :
  TESTDB
  APPHDL  : 0-4365               APPID:
  172.22.115.109.36790.181214185114
  AUTHID  : TESTUSER             HOSTNAME: hostname
  EDUID   : 174                  EDUNAME: db2agnts (TESTDB) 0
  FUNCTION: DB2 UDB, buffer pool services,
  sqlbUnchainBPDFromBucket, probe:374
  DATA #1 : String, 159 bytes
  NON-FATAL ASSERTION FAILED!!!ASSERTION EXPRESSION:
  bGroupPtr->hbGroup.header.groupLatch.isHeldX()
  SOURCE FILE NAME: sqlbfix_misc.C
  SOURCE FILE LINE NUMBER: 374
  DATA #2 : signed integer, 4 bytes
  -1
  DATA #3 : Buffer page descriptor, PD_TYPE_SQLB_BPD, 112 bytes
  << snip >>
  
  2018-12-14-19.54.19.967475+060 E20824941E3180        LEVEL:
  Severe (OS)
  PID     : 59071                TID : 140251481761536 PROC :
  db2sysc 0
  INSTANCE: db2inst1             NODE : 000            DB   :
  TESTDB
  APPHDL  : 0-4365               APPID:
  172.22.115.109.36790.181214185114
  AUTHID  : TESTUSER             HOSTNAME: hostname
  EDUID   : 174                  EDUNAME: db2agnts (TESTDB) 0
  FUNCTION: DB2 UDB, SQO Latch Tracing,
  SQLO_SLATCH_CAS64::releaseConflict, probe:300
  MESSAGE :
  ZRC=0x870F00FB=-2029059845=SQLO_SLATCH_ERROR_HELDX_WITH_SHARED_H
  OLDERS
            "shared latch found with both exclusive and shared
  holders.  Latch likely corrupt."
  CALLED  : OS, -, unspecified_system_function
  DATA #1 : String, 39 bytes
  Attempting to unlock an invalid latch:
  DATA #2 : File name, 16 bytes
  sqloLatchCAS64.C
  DATA #3 : Source file line number, 8 bytes
  1055
  DATA #4 : Codepath, 8 bytes
  0
  DATA #5 : String, 135 bytes
  0x00007F8F49DD37A8: {
     held X: 1
     reserved for X: 0
     shared holders: 14248
     firstSharIndex: 0x18F49D
     firstExclIndex: 0x3F
  }
  << snip >>
  
  The stack will look like this:
  
  <StackTrace>
  -----FUNC-ADDR---- ------FUNCTION + OFFSET------
  0x00007F90E390BF85
  _Z25ossDumpStackTraceInternalmR11OSSTrapFileiP7siginfoPvmm +
  0x0385
          (/home/db2inst1/sqllib/lib64/libdb2osse.so.1)
  0x00007F90E390BB8C ossDumpStackTraceV98 + 0x002c
          (/home/db2inst1/sqllib/lib64/libdb2osse.so.1)
  0x00007F90E3907C2D _ZN11OSSTrapFile6dumpExEmiP7siginfoPvm +
  0x00fd
          (/home/db2inst1/sqllib/lib64/libdb2osse.so.1)
  0x00007F90E9FC6114 sqlo_trce + 0x0404
          (/home/db2inst1/sqllib/lib64/libdb2e.so.1)
  0x00007F90EA050299 sqloEDUCodeTrapHandler + 0x02b9
          (/home/db2inst1/sqllib/lib64/libdb2e.so.1)
  0x00007F90EFED1680 address: 0x00007F90EFED1680 ; dladdress:
  0x00007F90EFEC2000 ; offset in lib: 0x000000000000F680 ;
          (/lib64/libpthread.so.0)
  0x00007F90E2B00207 gsignal + 0x0037
          (/lib64/libc.so.6)
  0x00007F90E2B018F8 abort + 0x0148
          (/lib64/libc.so.6)
  0x00007F90E7FB6C7D sqloExitEDU + 0x045d
          (/home/db2inst1/sqllib/lib64/libdb2e.so.1)
  0x00007F90E93D5906 _Z10sqle_panici + 0x0696
          (/home/db2inst1/sqllib/lib64/libdb2e.so.1)
  0x00007F90E9FC39EB
  _ZNK17SQLO_SLATCH_CAS6420dumpDiagInfoAndPanicEPKcjmmlmiS1_mi +
  0x02bb
          (/home/db2inst1/sqllib/lib64/libdb2e.so.1)
  0x00007F90EB034CA1 _ZN17SQLO_SLATCH_CAS6415releaseConflictEv +
  0x03b1
          (/home/db2inst1/sqllib/lib64/libdb2e.so.1)
  0x00007F90EAF420B0 _Z13sqlbUnfixPageP11SQLB_FIX_CB + 0x09a0
          (/home/db2inst1/sqllib/lib64/libdb2e.so.1)
  0x00007F90E8583DF2
  _Z13sqlsUnfixPageP10SQLS_SLDESP14SQLD_FILE_INFOm + 0x00b2
          (/home/db2inst1/sqllib/lib64/libdb2e.so.1)
  0x00007F90E8587D54 _Z8sqlsfshpP8sqeAgentP10SQLS_SLDES + 0x0f44
          (/home/db2inst1/sqllib/lib64/libdb2e.so.1)
  0x00007F90E8574113 _Z7sqlsendP8sqeAgentP10SQLS_SLDESi + 0x0053
          (/home/db2inst1/sqllib/lib64/libdb2e.so.1)
  

Local fix

Problem summary

• ****************************************************************
  * USERS AFFECTED:                                              *
  * ALL                                                          *
  ****************************************************************
  * PROBLEM DESCRIPTION:                                         *
  * See Error Description                                        *
  ****************************************************************
  * RECOMMENDATION:                                              *
  * Upgrade to Db2 11.1 Mod 4 Fixpack 5 or higher                *
  ****************************************************************
  

Problem conclusion

• First fixed in Db2 11.1 Mod 4 Fixpack 5
  

Temporary fix

Comments

APAR Information

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

  IT27664

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

Fix information

• Fixed component name

  DB2 FOR LUW

• Fixed component ID

  DB2FORLUW

Applicable component levels

• RB10 PSN

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