|
Problem IC97719
|
Status: Closed |
UNDER HIGH CONCURRENCY THE FAST INTEGER SORT ( FIS ) FEATURE CAN CAUSE HIGH LATCH CONTENTION AND PERFORMANCE DEGRADATION |
| product: |
DB2 FOR LUW / DB2FORLUW / A10 - DB2 |
| Problem description: |
The new Fast Integer Sort ( FIS ) optimization in this version
can cause high latch contention which is turn can cause scaling
issues for the database server.
The latch contention is observed on the latch
SQLO_LT_SMemSet__MemLatchType__latch
It can be clearly observed in db2pd -latches or if the utility
db2latchtrace is used.
The stacks are:
_ZN11SMemSubPool11releaseCSGsEb + 0x83
sqloFreeMemorySubPool + 0xE9
_Z17sqlrifisFreeHeapsP8sqlrr_cbP9sqlri_tao + 0x8F
_Z13sqlrifisCloseP8sqlrr_cbP9sqlri_tao + 0x10D
_Z8sqlridrpP8sqlrr_cbP9sqlri_tao + 0xBE
_Z15sqlricls_simpleP8sqlrr_cbil + 0x1D5E
_Z27sqlrr_process_close_requestP8sqlrr_cbiiii + 0xA03
_Z17sqlrr_fetch_errorP8sqlrr_cbP14db2UCinterfaceP15db2UCCursorIn
foii + 0x2FC
OR
sqloCreateMemorySubPool + 0xD7
_Z12sqlrifisInitP8sqlrr_cbP10sqlri_iudo + 0x2A5
_Z9sqlrifis2P8sqlrr_cb + 0xAF8
_Z8sqlischfP7SQLI_CBtj + 0x1E16
_Z8sqlischfP7SQLI_CBtj + 0x1110
_Z7sqlirdkP8sqeAgentP10SQLI_IXPCRP9SQLD_IXCBmP8SQLD_KEYP12SQLI_K
EYDATAP9sqli_scanPi + 0x7D6
_Z14sqldIndexFetchP8SQLD_CCBP8SQLZ_RID + 0x13B |
| Problem Summary: |
****************************************************************
* USERS AFFECTED: *
* ALL *
****************************************************************
* PROBLEM DESCRIPTION: *
* See Error Description *
****************************************************************
* RECOMMENDATION: *
* Upgrade to DB2 v10.1 FP4 or apply the suggested workaround *
**************************************************************** |
| Local Fix: |
Currently, there's a workaround to turn off this feature
completely using the following registry setting.
db2set DB2_TCG_DEFAULT_OPTIONS="set num_page_fast_int_sort 0"
This will revert back to original behavior prior to the new
feature. |
| available fix packs: |
DB2 Version 10.1 Fix Pack 4 for Linux, UNIX, and Windows
DB2 Version 10.1 Fix Pack 6 for Linux, UNIX, and Windows
|
| Solution |
Fixed in DB2 v10.1 FP4 |
| Workaround |
not known / see Local fix |
| BUG-Tracking |
forerunner : APAR is sysrouted TO one or more of the following: IC98355
follow-up : |
| Timestamps |
Date - problem reported :
Date - problem closed :
Date - last modified :
| 15.11.2013
05.03.2014
05.03.2014 |
| Problem solved at the following versions (IBM BugInfos) |
|
| Problem solved according to the fixlist(s) of the following version(s) |
| 10.1.0.4
|
 |
