IT37980: LOCK ESCALATION OCCURS IN PURESCALE WHEN DB2_AVOID_LOCK_ESCALATION IS SET

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

APAR status

• Closed as program error.

Error description

• Lock escalation might still occur in pureScale environment,
  even when DB2_AVOID_LOCK_ESCALATION register variable
  has been set to ON.  This occurs when the lock escalation was
  caused by the global lock list becoming full.
  
  You can see the following information from the db2diag.log when
  the problem occurs:
  
  2021-06-05-01.57.05.264636+540 I256221E655          LEVEL: Info
  PID     : 99546                TID : 70350482108768 PROC :
  db2sysc 0
  INSTANCE: db2inst1             NODE : 000           DB   : xxxx
  APPHDL  : 0-63462              APPID: xxxxxxxxxxxxx
  UOWID   : 1                    ACTID: 1244527
  AUTHID  : xxxxxx               HOSTNAME: xxxxxxx
  EDUID   : 42149                EDUNAME: db2agent (xxxxxx) 0
  FUNCTION: DB2 UDB, lock manager, sqlpUpdateMemStatus, probe:611
  DATA #1 :
  Locking memory management: GLM-memory low.
  Escalation threshold activated.
  GLM-lock list size = 18040822
  GLM-lock list available = 1504296
  
  2021-06-05-01.57.05.265294+540 E256877E1476         LEVEL: Info
  PID     : 99546                TID : 70366625984864 PROC :
  db2sysc 0
  INSTANCE: db2inst1             NODE : 000           DB   : xxxx
  APPHDL  : 0-63256              APPID: xxxxxxxxxxxxx
  UOWID   : 1                    ACTID: 6740552
  AUTHID  : xxxxxx               HOSTNAME: xxxxxxx
  EDUID   : 42098                EDUNAME: db2agent (xxxxxxx) 0
  FUNCTION: DB2 UDB, data management, sqldEscalateLocks, probe:1
  MESSAGE : ADM5501I  The database manager is performing lock
  escalation. The
            affected application is named "xxxxx", and is
  associated with the
            workload name "SYSDEFAULTUSERWORKLOAD" and application
  ID
            "10.7.18.26.52616.210604162246"  at member "0". The
  total number of
            locks currently held is "16", and the target number of
  locks to hold
            is "8". The current statement being executed is
  "xxxxxxxxxxxxxxxxxx".
            Reason code: "3"
  DATA #1 : Hex integer, 8 bytes
  0x830000000004003C
  

Local fix

Problem summary

• ****************************************************************
  * USERS AFFECTED:                                              *
  * AIX/LINUX                                                    *
  ****************************************************************
  * PROBLEM DESCRIPTION:                                         *
  * See Error Description                                        *
  ****************************************************************
  * RECOMMENDATION:                                              *
  * Upgrade to db2 v11.1.4.7                                     *
  ****************************************************************
  

Problem conclusion

• Upgrade to db2 v11.1.4.7
  

Temporary fix

Comments

APAR Information

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

  IT37926

• 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 PSY

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