|
Problem IC65769
|
Status: Closed |
REDESIGN LOCKING MECHANISM FOR DB2 RECOVERY HISTORY FILE ACCESS |
| product: |
DB2 FOR LUW / DB2FORLUW / 970 - DB2 |
| Problem description: |
Concurrent access to the DB2 recovery history file is currently
accomplished by using operating system semaphore primitives -
semop() calls.
Two different potential problem areas were identified when
accessing/locking the history file in parallel via it's
several API's:
1) Frequent semop() calls may cause performance issues (high
CPU usage) especially if the history file is very large.
2) There is a small timing window where DB2 may hang when
a process is killed while initializing the semaphore.
The fix for this APAR will ensure that the above problems are
avoided by redesigning the internal locking mechanism used by
DB2. |
| Problem Summary: |
****************************************************************
* USERS AFFECTED: *
* all version 9 *
****************************************************************
* PROBLEM DESCRIPTION: *
* see error description above *
****************************************************************
* RECOMMENDATION: *
* Upgrade to Version 9.7 Fix Pack 2 *
**************************************************************** |
| Local Fix: |
Avoid frequent parallel access to the recovery history file.
and/or
try to prune the recovery history file on regular intervals to
keep it's size small. |
| available fix packs: |
DB2 Version 9.7 Fix Pack 2 for Linux, UNIX, and Windows
DB2 Version 9.7 Fix Pack 3 for Linux, UNIX, and Windows
DB2 Version 9.7 Fix Pack 3a for Linux, UNIX, and Windows
DB2 Version 9.7 Fix Pack 4 for Linux, UNIX, and Windows
DB2 Version 9.7 Fix Pack 5 for Linux, UNIX, and Windows
DB2 Version 9.7 Fix Pack 6 for Linux, UNIX, and Windows
DB2 Version 9.7 Fix Pack 7 for Linux, UNIX, and Windows
DB2 Version 9.7 Fix Pack 8 for Linux, UNIX, and Windows
DB2 Version 9.7 Fix Pack 9a for Linux, UNIX, and Windows
DB2 Version 9.7 Fix Pack 9 for Linux, UNIX, and Windows
DB2 Version 9.7 Fix Pack 10 for Linux, UNIX, and Windows
|
| Solution |
Problem was first fixed in Version 9.7 Fix Pack 2 |
| Workaround |
not known / see Local fix |
| Timestamps |
Date - problem reported :
Date - problem closed :
Date - last modified :
| 25.01.2010
14.12.2010
14.12.2010 |
| Problem solved at the following versions (IBM BugInfos) |
9.7.FP2
|
| Problem solved according to the fixlist(s) of the following version(s) |
| 9.7.0.2
|
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