|
Problem IC65368
|
Status: Closed |
MULTIPLE AGENTS CALLING FLUSH OPTIMIZATION PROFILE CACHE WHILE A PROFILE IS IN USE CAN RESULT IN A LOCK/LATCH DEADLOCK |
| product: |
DB2 FOR LUW / DB2FORLUW / 950 - DB2 |
| Problem description: |
An agent calling FLUSH OPTIMIZATION PROFILE CACHE and an agent
using an OPT profile can get into a "deadlock" of sorts with one
agent waiting on a latch while the other is waiting on a lock.
This looks very similar to APAR IZ26477, but is the result of
the FLUSH OPTIMIZATION PROFILE CACHE instead of an Online Reorg.
In the latch tracking part of the stack files you will see:
<<<< File = <thread_1> >>>>
timestamp: 2009-09-16-14.56.27.914060
Holding Latch type: (SQLO_LT_sqlrlc_anchor_common__anchor_latch)
- Address: (256cd9b4c), Line: 71, File:
/view/db2_v91fp3a_sun64_s070914/vbs/engn/include/sqlrlc_inlines.
h
Holding Latch type: (SQLO_LT_sqlrlc_anchor_common__lru_latch) -
Address: (256cd9b50), Line: 239, File: sqlrlc_flush.C
<<<< File = <thread_2> >>>>
timestamp: 2009-09-16-14.51.15.944435
Waiting on latch type:
(SQLO_LT_sqlrlc_anchor_common__anchor_latch) - Address: (
256cd9b4c), Line: 1042, File: sqlrlc_request_usage.C
timestamp: 2009-09-16-14.56.23.561822
Waiting on latch type:
(SQLO_LT_sqlrlc_anchor_common__anchor_latch) - Address: (
256cd9b4c), Line: 1042, File: sqlrlc_request_usage.C
and the db2pd output will show:
Applications:
Address AppHandl [nod-index] NumAgents CoorPid
Status C-AnchID C-StmtUID L-AnchID L-StmtUID
Appid
0x00000002006FB860 236 [000-00236] 1 <thread_1>
Lock-wait 155 1 228 1
*LOCAL.db2inst1.090916045036
0x00000002005DF800 192 [000-00192] 1 <thread_2>
UOW-Executing 0 0 6 1
*LOCAL.db2inst1.090916044452
So, thread_1 is holding a latch thread_2 needs and thread_2
needs the lock that thread_1 is holding. |
| Problem Summary: |
Users Affected: Any using the flush optimization profile cache
command repeatedly.
Problem Description: MULTIPLE AGENTS CALLING FLUSH OPTIMIZATION
PROFILE CACHE WHILE PROFILE IS IN USE CAN RESULT IN A LOCK/LATCH
DEADLOCK
Problem Summary: see above |
| Local Fix: |
|
| available fix packs: |
DB2 Version 9.5 Fix Pack 6a for Linux, UNIX, and Windows
DB2 Version 9.5 Fix Pack 7 for Linux, UNIX, and Windows
DB2 Version 9.5 Fix Pack 8 for Linux, UNIX, and Windows
DB2 Version 9.5 Fix Pack 9 for Linux, UNIX, and Windows
DB2 Version 9.5 Fix Pack 10 for Linux, UNIX, and Windows
|
| Solution |
Problem was first fixed in Version 9.5 FixPak 6 |
| Workaround |
n/a |
| Timestamps |
Date - problem reported :
Date - problem closed :
Date - last modified :
| 01.01.2010
07.10.2010
07.10.2010 |
| Problem solved at the following versions (IBM BugInfos) |
9.5.
|
| Problem solved according to the fixlist(s) of the following version(s) |
