A fix is available
APAR status
Closed as program error.
Error description
MSTR SRB time is increased a lot after migrating to V10. There's an internal growth of a storage cache, the management of that cache is causing MSTR CPU to be consumed.
Local fix
Problem summary
**************************************************************** * USERS AFFECTED: All DB2 HDBAA10 V10 users. * **************************************************************** * PROBLEM DESCRIPTION: High DB2 MSTR SRB CPU time is observed * * and some STATs fields not externalized * * to IFCID1. * **************************************************************** * RECOMMENDATION: INSTALL PTF * **************************************************************** During DB2 storage contraction, pool FREE or pool RESET of 64bit pools, high MSTR CPU time may be observed if the pool contains used blocks more than 8K in size. This CPU increase may occur at commit or at thread deallocation or both, especially when the storage is contained in the CTV64STP or other thread pools which persist in cached threads beyond deallocation. While trying to analyze the reason for the CPU increase, it was observed that fields QSST_RSMAX_WARN, QSST_P64DISNUM, QSST_P64DISBLK, QSST_P64DISPGS, and QSST_CONTSTOR_NUM were missing from IFCID1.
Problem conclusion
The logic for discarding the REAL frame backing for 64bit pools is changed to detect when blocks do not contain backed pages since the last time the discard was done. This may occur during pool contraction or thread commit or deallocation. This avoids the IARV64 DISCARDDATA call to z/OS unless there are backed pages indicated. Also, the missing fields were externalized to the IFCID1.
Temporary fix
********* * HIPER * *********
Comments
APAR Information
APAR number
PM65360
Reported component name
DB2 OS/390 & Z/
Reported component ID
5740XYR00
Reported release
A10
Status
CLOSED PER
PE
NoPE
HIPER
YesHIPER
Special Attention
NoSpecatt
Submitted date
2012-05-23
Closed date
2012-07-10
Last modified date
2012-08-08
APAR is sysrouted FROM one or more of the following:
APAR is sysrouted TO one or more of the following:
UK80191
Modules/Macros
DSNSCON2 DSNSQST DSNSVSVP
Fix information
Fixed component name
DB2 OS/390 & Z/
Fixed component ID
5740XYR00
Applicable component levels
RA10 PSY UK80191
UP12/07/27 P F207
Fix is available
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Document Information
Modified date:
08 August 2012