|
Problem IT02258
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Status: Closed |
ONLINE BACKUP PERFORMANCE DEGRADATION AND ABNORMAL BACKUP IMAGE FILE SIZE VARIATIONS IN V10.1 |
| product: |
DB2 FOR LUW / DB2FORLUW / A50 - DB2 |
| Problem description: |
in v10.1, an Online Backup may perform poorer then previous
releases. Also, there may be an abnormally large variance in
the size of the backup sequence files.
When more then one tablespace exist, Online Backup will
parallelize the processing of tablespaces. Before reading
extents for a tablespace in parallel, Backup must flush dirty
bufferpool
pages for this tablespace to disk. Prior to v10.1 this flush
was performed in
parallel by the backup db2bm edus. In v10.1 this action is
performed in serial by the backup db2agent edu. If flushing of
the bufferpools takes a relatively long time (because the
bufferpools contain many dirty pages, or there is a lot of other
concurrent transaction activity) then it will take longer for
Backup's parallel db2bm edus to begin processing some
tablespaces.
Also, when more then one path is specified in the Online Backup
command, this defect can result in abnormally large variations
in the size of the backup sequence files, usually one being
much larger then others (small variations are normal).
These problems do not affect releases prior to 10.1. |
| Problem Summary: |
****************************************************************
* USERS AFFECTED: *
* All *
****************************************************************
* PROBLEM DESCRIPTION: *
* See Error Description *
****************************************************************
* RECOMMENDATION: *
* Upgrade to inclusive fixpack. *
**************************************************************** |
| Local Fix: |
One potential method to help alleviate the issue is to decrease
the Backup PARALLELISM value. Another potential method to help
alleviate the issue is to disable TRACKMOD configuration
parameter (if you to do not need incremental or delta backups). |
| available fix packs: |
DB2 Cancun Release 10.5.0.4 (also known as Fix Pack 4) for Linux, UNIX, and Windows
DB2 Version 10.5 Fix Pack 9 for Linux, UNIX, and Windows
|
| Solution |
|
| Workaround |
not known / see Local fix |
| Timestamps |
Date - problem reported :
Date - problem closed :
Date - last modified :
| 05.06.2014
08.09.2014
08.09.2014 |
| Problem solved at the following versions (IBM BugInfos) |
|
| Problem solved according to the fixlist(s) of the following version(s) |
| 10.5.0.4
|
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