DB2 FOR LUW / DB2FORLUW / 970 - DB2

APAR IC69285 added a limit on back ground system applications 
(such as asynchronous index cleanup, admin task scheduler, 
health monitor) in v9.7 fp4. This limit is determined 
dynamically based on workload and sometimes it is too low 
resulting in too many SQL1226N errors being encountered. 
When the limit is reached, a new background task cannot be 
started until others are finished. 
 
Fast writer EDUs are background system applications that are 
used by new event monitor types added in DB2 v9.7. The number of 
fast writer EDUs started at database activation is based on the 
number of logical CPUs and logical nodes hosted on a machine. 
Due to this APAR, these fast writer EDUs are being counted 
towards the limit on background system applications which can 
mean that other background applications cannot run as they will 
receive a SQL1226N error. 
 
In this example, the autonomic computing daemon that is trying 
to connect to the database to run back ground jobs. 
 
 
2011-04-25-12.00.44.655369-240 I2051096A465       LEVEL: Info 
PID     : 24183550             TID  : 1029        PROC : db2sysc 
INSTANCE: db2inst1           NODE : 000 
EDUID   : 1029                 EDUNAME: db2ipccm 
FUNCTION: DB2 UDB, base sys utilities, 
sqeAgentServices::RequestAgentForAppl, probe:1459 
MESSAGE : ZRC=0xFFFFFB36=-1226 
DATA #1 : <preformatted> 
The number of background tasks has reached the limit of 61, will 
try again later. 
0 200 80 80 80 78 2

**************************************************************** 
* USERS AFFECTED:                                              * 
* This APAR is more likely to be hit on machines with more     * 
* than 8 processors per logical node.                          * 
**************************************************************** 
* PROBLEM DESCRIPTION:                                         * 
* See above.                                                   * 
**************************************************************** 
* RECOMMENDATION:                                              * 
* Upgrade to v9.7 fp5.                                         * 
****************************************************************

Disable the limit on background system applications 
using the following registry variable setting. 
 
db2set DB2_PMODEL_SETTINGS=MAX_BACKGROUND_SYSAPPS:500 
 
This is a dynamic registry variable setting that will be picked 
up immediately without restarting the instance.

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
 

In v9.7 fp5, the limit on background system applications is 
turned off by default which was the behaviour in v9.7 fp3 or 
earlier. 
A fixed limit on background system applications can be set with 
the following registry variable: 
 
DB2_PMODEL_SETTINGS=MAX_BACKGROUND_SYSAPPS:<num> 
 
where num is the limit. A reasonable number might be 100. The 
instance must be restarted to pick up a change to this 
registry variable.

keiner bekannt / siehe Local-Fix

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

02.05.2011
16.12.2011
16.12.2011

9.7.FP3,
9.7.FP5,
9.7.FP5