DB2 FOR LUW / DB2FORLUW / 970 - DB2

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.

**************************************************************** 
* 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                                      * 
****************************************************************

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 9 for Linux, UNIX, and Windows
 DB2 Version 9.7 Fix Pack 9a for Linux, UNIX, and Windows
 DB2 Version 9.7 Fix Pack 10 for Linux, UNIX, and Windows
 

First fixed in DB2 V9.5 FP7

keiner bekannt / siehe Local-Fix

Datum - Problem gemeldet    :
Datum - Problem geschlossen :
Datum - der letzten Änderung:

21.03.2011
21.03.2011
21.03.2011

9.5.FP7