|
Problem IC67696
|
Status: Closed |
ONLINE BACKUP PERFORMANCE SLOW AT V9.1FP7 if tablespaces have many containers |
| product: |
DB2 FOR LUW / DB2FORLUW / 980 - DB2 |
| Problem description: |
Online backup at V9.1FP7 slow compared to previous versions
if the tablespaces have many containers (typically 32 or more).
A sympton is that the read I/O on the server is not being driven
intensively.
Analysing stack from a db2pd -stack will show that only 1 of the
db2 prefetchers (db2pfchr) is doing work, whereas the remainder
are
idle. That is there would be 1 stack similar to the following :
Stack:
======================
0x090000000006226C pread64 + 0x34
0x09000000030036CC sqloReadBlocks + 0x18
0x0900000002B94E54
sqlbReadBlocks__FP16SqlbOpenFileInfoPvlUlUiPUlP12SQLB_GLOBALS +
0x100
0x090000000300D1DC
@28@sqlbDMSReadContainerData__FP17SQLB_DIRECT_IO_CBP13SQLB_MAP_I
NFOP16SqlbOpenFileInfoPcP12SQLB_GLOBALS + 0x28
0x090000000300CF1C sqlbDMSDirectRead__FP17SQLB_DIRECT_IO_CB +
0x400
0x0900000002B9018C sqlbDirectRead__FP17SQLB_DIRECT_IO_CB +
0x10C
0x090000000390E7AC
sqlbServiceDirectReadRequest__FP11SQLB_pfMisc + 0x684
0x09000000029E7660 sqlbPFPrefetcherEntryPoint__FPcUi + 0x444
0x0900000002FB610C
sqloCreateEDU__FPFPcUi_vPcUlP13SQLO_EDU_INFOPi + 0x268
0x0900000002F6956C @49@sqloRunGDS__Fv + 0xDC
with all the other db2 prefetchers having stacks similar to the
following :
Stack:
======================
0x09000000001D6394 msgrcv + 0xB0
0x09000000030850FC .sqloCSemP_fdprpro_clone_929 + 0x144
0x0900000003085328
.sqlbpfRemoveFromQ__FP12SQLB_pfQUEUEUlPP14SQLB_pfRequestP8sqledb
cbPP12SQLD_OBJ_HDLP12SQLB_GLOBALS_fdprpro_clone_93 + 0x15C
0x0900000003085CB0 sqlbPFPrefetcherEntryPoint__FPcUi + 0x100
0x0900000002FB610C
sqloCreateEDU__FPFPcUi_vPcUlP13SQLO_EDU_INFOPi + 0x268
0x0900000002F6956C @49@sqloRunGDS__Fv + 0xDC
0x0900000002FB4D0C sqloInitEDUServices + 0x178
0x0900000002FAED84
@49@sqloSystemControllerMain__FCUiPFv_iPFi_vPPvCPi + 0x33C
0x0900000002FB0438 sqloRunInstance + 0xA8
0x00000001000029F8 DB2main + 0x930 |
| Problem Summary: |
****************************************************************
* USERS AFFECTED: *
* ALL *
****************************************************************
* PROBLEM DESCRIPTION: *
* See error description *
****************************************************************
* RECOMMENDATION: *
* Upgrade to DB2 V9.8 FP3 *
**************************************************************** |
| Local Fix: |
Rearrange the tablespaces so that there are less containers per
tablespace - typically less than 32. |
| available fix packs: |
DB2 Version 9.8 Fix Pack 3 for Linux, UNIX, and Windows
DB2 Version 9.8 Fix Pack 4 for AIX and Linux
DB2 Version 9.8 Fix Pack 5 for AIX and Linux
|
| Solution |
Problem first fixed in DB2 V9.8 FP3 |
| Workaround |
not known / see Local fix |
| Timestamps |
Date - problem reported :
Date - problem closed :
Date - last modified :
| 07.04.2010
17.01.2011
17.01.2011 |
| Problem solved at the following versions (IBM BugInfos) |
9.8.FP3
|
| Problem solved according to the fixlist(s) of the following version(s) |
| 9.8.0.3
|
 |
