IT35566: MEMORY BLOCK FREED TWICE IN SQLOFMBLKEX

Db2 Version 11.1 Mod 4 Fix Pack 7 for Linux, UNIX, and Windows

APAR status

• Closed as program error.

Error description

• When running a SELECT statement on a DPF, and there is a
  shortage of memory, the engine traps as it attempts to free the
  memory twice
  
  Here's the stack when we got the problem:
  0x00007FFFEDF7085E sqle_panic(int) + 0x021e
  0x00007FFFEFD8BAD5 sqlofmblkEx + 0x07a5
  0x00007FFFF047C829 sqlrkrpc_send_reply(sqlrr_cb*, SQLKD_CB*,
  SQLR_RPCMESSAGE*, sqlca*, int, SQLR_BDSREPLY_STATE*) + 0x03f9
  0x00007FFFF0471286 sqlrr_rpc_router(sqlrr_cb*) + 0x0326
  0x00007FFFF046FC5E sqlrr_subagent_router(sqeAgent*,
  SQLE_DB2RA_T*) + 0x104e
  0x00007FFFEDF49546 address: 0x00007FFFEDF49546 ; dladdress:
  0x00007FFFE8934000 ; offset in lib: 0x0000000005615546 ;
  0x00007FFFEDF47DE0 sqleProcessSubRequest(sqeAgent*) + 0x03e0
  0x00007FFFEDF7D057 sqeAgent::RunEDU() + 0x05d7
  0x00007FFFF18B6F5E sqzEDUObj::EDUDriver() + 0x01be
  0x00007FFFEFDD4A6A sqloEDUEntry + 0x057a
  0x00007FFFF79C5EA5 address: 0x00007FFFF79C5EA5 ; dladdress:
  0x00007FFFF79BE000 ; offset in lib: 0x0000000000007EA5 ;
  0x00007FFFE73DC96D clone + 0x006d
  
  Here's the messages in db2diag.log:
  
  2021-01-12-02.41.22.451179-300 I25150E748 LEVEL: Warning
  PID : 10439 TID : 140725048043264 PROC : db2sysc 2
  INSTANCE: db2inst1 NODE : 002 DB : MYDB
  APPHDL : 1-35532 APPID: X.X.X.X.1.58761.210111115203
  AUTHID : USER1  HOSTNAME: myhost
  EDUID : 2682 EDUNAME: db2agntp (MYDB) 2
  FUNCTION: DB2 UDB, SQO Memory Management,
  SMemBasePool::requestToGrowPhysicalSize, probe:110
  MESSAGE : Memory Allocation failed due to DB2_MEM_HEAP_MAX_PCT.
  DATA #1 : reqChunks, PD_TYPE_REQ_CHUNKS, 4 bytes
  4
  DATA #2 : Pool type, PD_TYPE_POOL_TYPE, 4 bytes
  1
  DATA #3 : unsigned integer, 8 bytes
  30
  DATA #4 : unsigned integer, 8 bytes
  4635903590
  
  2021-01-12-02.41.32.041110-300 I25899E554 LEVEL: Severe
  PID : 10439 TID : 140725048043264 PROC : db2sysc 2
  INSTANCE: db2inst1 NODE : 002 DB : MYDB
  APPHDL : 1-35532 APPID: X.X.X.X.1.58761.210111115203
  AUTHID : USER1  HOSTNAME: myhost
  EDUID : 2682 EDUNAME: db2agntp (MYDB) 2
  FUNCTION: DB2 UDB, relation data serv, sqlrr_signal_handler,
  probe:100
  MESSAGE : DIA0505I Execution of a component signal handling
  function has begun.
  
  2021-01-12-02.41.32.057911-300 I27146E618 LEVEL: Severe
  PID : 10439 TID : 140725048043264 PROC : db2sysc 2
  INSTANCE: db2inst1 NODE : 002 DB : MYDB
  APPHDL : 1-35532 APPID: X.X.X.X.1.58761.210111115203
  AUTHID : USER1  HOSTNAME: myhost
  EDUID : 2682 EDUNAME: db2agntp (MYDB) 2
  FUNCTION: DB2 UDB, relation data serv, sqlrr_dump_sibling,
  probe:100
  MESSAGE : * NOTE: NULL pentptr ... no pkgentry data
  DATA #1 : Hexdump, 1 bytes
  0x00007FFFF43F5DCC : 2A *
  

Local fix

Problem summary

• ****************************************************************
  * USERS AFFECTED:                                              *
  * all                                                          *
  ****************************************************************
  * PROBLEM DESCRIPTION:                                         *
  * See Error Description                                        *
  ****************************************************************
  * RECOMMENDATION:                                              *
  * Upgrade to 11.1.4.7                                          *
  ****************************************************************
  

Problem conclusion

• Upgrade to 11.1.4.7
  

Temporary fix

Comments

APAR Information

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

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

  IT36323

Fix information

• Fixed component name

  DB2 FOR LUW

• Fixed component ID

  DB2FORLUW

Applicable component levels

• RB10 PSN

     UP

• RB10 PSY

     UP