|
Problem IC98355
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Status: Closed |
UNDER HIGH CONCURRENCY THE FAST INTEGER SORT ( FIS ) FEATURE CAN CAUSE HIGH LATCH CONTENTION AND PERFORMANCE DEGRADATION |
| product: |
DB2 FOR LUW / DB2FORLUW / A50 - 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: *
* Update to 10.5.0.3 *
**************************************************************** |
| 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 10.5 Fix Pack 3 for Linux, UNIX, and Windows
DB2 Version 10.5 Fix Pack 3a for Linux, UNIX, and Windows
DB2 Cancun Release 10.5.0.4 (also known as Fix Pack 4) for Linux, UNIX, and Windows
DB2 Version 10.5 Fix Pack 9 for Linux, UNIX, and Windows
|
| Solution |
Problem Fixed In 10.5.0.3 |
| Workaround |
not known / see Local fix |
| Timestamps |
Date - problem reported :
Date - problem closed :
Date - last modified :
| 16.12.2013
28.02.2014
28.02.2014 |
| Problem solved at the following versions (IBM BugInfos) |
|
| Problem solved according to the fixlist(s) of the following version(s) |
| 10.5.0.3
|
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| 10.5.0.3
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