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Problem IC71594
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Status: Closed |
DB2LOGGR CHECKS FOR DYNAMIC REGISTRY DB2_DPS_LIMIT2 TOO OFTEN, MAY CAUSE PERFORMANCE ISSUES ON LARGE DPF INSTANCES. |
| product: |
DB2 FOR LUW / DB2FORLUW / 950 - DB2 |
| Problem description: |
An incredible amount of uncached registry reads was noticed from
db2 traces - 1315 in 120 seconds, almost 10 times a second on
each physical partition (8 MLNs). Uncached read means we are
checking dynamic registry value, - we actually go to registry
file on disk, lock it, read from it, unlock it. Since in DPF
registry files are on NFS, this is too much overhead and too
high of a price for using dynamic registries. Extrapolating to
say for example 32 servers, - we attempt to read from global
registry 320 times a second.
This APAR fixes the issue of uncached registry reads. |
| Problem Summary: |
****************************************************************
* USERS AFFECTED: *
* DB2 V9.5 *
****************************************************************
* PROBLEM DESCRIPTION: *
* An incredible amount of uncached registry reads was *
* noticedfromdb2 traces - 1315 in 120 seconds, almost 10 times *
* a secondoneach physical partition (8 MLNs). Uncached read *
* means we arechecking dynamic registry value, - we actually *
* go toregistryfile on disk, lock it, read from it, unlock it. *
* Since in DPFregistry files are on NFS, this is too much *
* overhead and toohigh of a price for using dynamic *
* registries. Extrapolatingtosay for example 32 servers, - we *
* attempt to read from globalregistry 320 times a second.This *
* APAR fixes the issue of uncached registry reads. *
****************************************************************
* RECOMMENDATION: *
* Upgrade to DB2 V9.5 FP7 *
**************************************************************** |
| Local Fix: |
|
| available fix packs: |
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 |
First fixed in DB2 V9.5 FP7 |
| Workaround |
not known / see Local fix |
| BUG-Tracking |
forerunner : APAR is sysrouted TO one or more of the following: IC75157
follow-up : |
| Timestamps |
Date - problem reported :
Date - problem closed :
Date - last modified :
| 30.09.2010
15.11.2010
15.11.2010 |
| Problem solved at the following versions (IBM BugInfos) |
9.5.FP7
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| Problem solved according to the fixlist(s) of the following version(s) |
| 9.1.0.7
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 |
| 9.5.0.7
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