DB2 - Problem description
| Problem IT08335 | Status: Closed |
PRIVATE MEMORY LEAK DURING CRASH RECOVERY, ROLLFORWARD, HADR FORCED TAKEOVER | |
| product: | |
DB2 FOR LUW / DB2FORLUW / A10 - DB2 | |
| Problem description: | |
A significant amount of private memory may be leaked during
crash recovery, rollforward, and hadr forced takeover activities
while processing logs. The leak is in private memory pool for a
db2agent, and will be indirectly freed when the agent terminates
or recycles. If the database stays active following the
vulnerable activity, the agent may remain associated with the
database for an extended period of time, and the accumulated
memory stays allocated.
The memory leak is in DB2 private memory, so any DB2 or OS
monitoring tool would show a marked increase in private memory
usage if the leak has a significant impact. For example, the
following would show a specific EDU with a large memory pool
usage amount :
select memory_pool_type, edu_id, memory_pool_used from
table(mon_get_memory_pool('PRIVATE',null,null)) where
memory_pool_type = 'PRIVATE' order by 3 descending fetch first 3
rows only
The following can be run on systems with ample free memory to
further validate the symptom
db2pd -memblocks pid=<db2sysc process ID> -file private.blocks
A large number of blocks similar to the following may be
observed :
PoolID PoolName BlkAge Size(Bytes) I LOC File
0 200 8192 1 366 418210772
0 201 8192 1 366 418210772
0 202 8192 1 366 418210772
...
"File" value is the important value to match. LOC value may not
be identical | |
| Problem Summary: | |
**************************************************************** * USERS AFFECTED: * * All DB2 systems are affected * **************************************************************** * PROBLEM DESCRIPTION: * * See Error Description * **************************************************************** * RECOMMENDATION: * * Upgrade to DB2 Version 10.1 Fix Pack 5 * **************************************************************** | |
| Local Fix: | |
Recycle database (force applications, deactivate database) | |
| Solution | |
Problem first fixed in DB2 Version 10.1 Fix Pack 5 | |
| Workaround | |
see Local Fix | |
| Timestamps | |
Date - problem reported : Date - problem closed : Date - last modified : | 15.04.2015 29.07.2015 29.07.2015 |
| Problem solved at the following versions (IBM BugInfos) | |
| Problem solved according to the fixlist(s) of the following version(s) | |
| 10.1.0.5 |
|