PROBLEM DESCRIPTION:
====================
When an Instance Memory limit is in effect, STMM may report a
failure to increase a consumer as follows :
2009-12-07-17.38.38.253963-480 I9251233A639 LEVEL: Warning
PID : 2203778 TID : 21131 PROC : db2sysc
0
INSTANCE: db2inst1 NODE : 000 DB : SAMPLE
APPHDL : 0-163 APPID: *LOCAL.DB2.091114224558
AUTHID : db2inst1
EDUID : 21131 EDUNAME: db2stmm (SAMPLE) 0
FUNCTION: DB2 UDB, Self tuning memory manager,
stmmCheckIfFreeMemoryIsEnoughForSizeIncr, probe:652
MESSAGE : ZRC=0xFFFFEC49=-5047
DATA #1 : String, 150 bytes
There is not enough free memory for size increase. Free memory
in pages:
Physical memory = 2012001, Instance memory = 628208, Database
memory = 461568
This is caused by an inconsistency in the treatment of excess
database overflow memory. STMM considers excess database
overflow memory as available instance memory, meaning it can be
used or reclaimed for any desired configuration increases.
Before performing any individual tuning increase, STMM performs
a sanity check to make sure there is still available instance
memory. The problem is that this check does not consider excess
overflow to be available instance memory. This discrepancy can
result in STMM failing to perform a planned
tuning increase.
Having enough excess database overflow memory to trigger this
problem is not common. It may occur, for example, when utilities
complete which were using more utility heap than configured
(this is allowed as utility heap is a soft limit).
The warning can be ignored. After performing tuning changes
(including any failed increase), database memory overflow is
retuned. This overflow tuning step releases excess database
overflow memory, and it will be available for any tuning
increases on the next STMM tuning cycle.
db2diag.log:
==========
2009-12-07-17.38.38.253963-480 I9251233A639 LEVEL: Warning
PID : 2203778 TID : 21131 PROC : db2sysc
0
INSTANCE: db2app NODE : 000 DB : APP
APPHDL : 0-163 APPID: *LOCAL.DB2.091114224558
AUTHID : NAGIOS
EDUID : 21131 EDUNAME: db2stmm (APP) 0
FUNCTION: DB2 UDB, Self tuning memory manager,
stmmCheckIfFreeMemoryIsEnoughForSizeIncr, probe:652
MESSAGE : ZRC=0xFFFFEC49=-5047
DATA #1 : String, 150 bytes
There is not enough free memory for size increase. Free memory
in pages:
Physical memory = 2012001, Instance memory = 628208, Database
memory = 461568 |
