DB2 FOR LUW / DB2FORLUW / 970 - DB2

When using DB2 Version 9.7 Fix Pack 6, Memory is consumed 
quickly in the DB2 private memory when an application uses the 
db2readlog API to extract log records (common in replication 
solutions). This leads to a severe memory leak. 
 
On DB2 Version 9.7 Fix Pack 6, private memory usage grows 
quickly on the DB2 server ( db2sysc or db2syscs.exe process ) 
when applications are initiating log read requests through the 
db2ReadLog API. 
 
There may be a wide variety of symptoms such as; 
 
    out of instance memory, 
    STMM detuning, 
    system paging, hangs or failover. 
 
An example of an application using the db2readlog api is IBMﾩ 
Infosphereﾩ Replication Server (Data propagator). There maybe 
other IBM or 3rd party 'Log reader' type applications which also 
uses this API. 
 
This problem was first introduced in DB2 Version 9.7 Fix Pack 6 
(9.7.0.6) 
 
To identify if you are hitting the issue: 
 
    Verify the DB2 Fixpack level by running the db2level command 
to ensure you are on DB2 9.7 Fix Pack 6 
 
2. Ensure that you are running an application that uses the 
db2readlog API to extract the LOG records. Application snapshot 
returns the application name. Example of applications using the 
db2readlog API are bg_realtime_server, asncap. 
 
Example of Application name as seen in the application snapshot 
ouput: 
 
Application name                           = ASNCAP.exe 
 
3. If you notice the system memory usage grows quickly, perform 
the following diagnosis to confirm you have encountered this 
issue: 
 
a) Gather application snapshots and verify if "Other Memory" is 
high (i.e. > 10MB) and is continuing to grow, 
 
Example entry as follows: 
Memory Pool Type                       = Other Memory 
        Current size (bytes)                = 719257600 
        High water mark (bytes)             = 720764928 
        Configured size (bytes)             = 8539602944 
 
b) Gather db2pd -memb pid= output. It will show an increasing 
number of allocations of size equal to LOGBUFSZ (database 
configuration parameter) with the file hash reference 419169217 
and location code 847 . 
 
Example entry as follows: 
Address            DataAddress        PoolID     PoolName 
BlockAge   Size(Bytes) TID         I LOC   File 
0x000000055D497FC8 0x000000055D497FE0 88         private 
39046 4096000     4896  1 847   419169217

**************************************************************** 
* USERS AFFECTED:                                              * 
* ALL                                                          * 
**************************************************************** 
* PROBLEM DESCRIPTION:                                         * 
* See Error Description                                        * 
**************************************************************** 
* RECOMMENDATION:                                              * 
* If the system is running the initial version of 9.7 FP6      * 
* (build number s120516 ) then upgrade to 9.7 FP6 build number * 
* s120629                                                      * 
****************************************************************

There is no Local Fix to the issue.

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 Version 9.7 Fix Pack 6 ( 9.7.0.6 ) dated 
July.3.2012  Build number = s120629

keiner bekannt / siehe Local-Fix

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

28.06.2012
16.07.2012
04.09.2012

9.7.0.6,
9.7.FP6