A fix is available
APAR status
Closed as new function.
Error description
Db2 12 code to support new function for utility datasets
Local fix
n/a
Problem summary
**************************************************************** * USERS AFFECTED: * * All Db2 12 for z/OS users. * **************************************************************** * PROBLEM DESCRIPTION: * * Large number of data sets opened * * concurrently by Db2 utilities could * * cause DSMAX to be hit and impact * * performance of other applications. * **************************************************************** * RECOMMENDATION: * **************************************************************** Db2 manages its concurrent data set opens against the DSMAX limit, dynamically opening and closing datasets as needed in LRU fashion to stay within the limit. Db2 COPY utility could open a large number of data sets and leave the datasets open when the utility completed. That could cause DSMAX to be hit and impact the performance of other applications.
Problem conclusion
Temporary fix
Comments
The dataset close processing logic has been improved to proactively close datasets that were opened solely for utility access. Db2 will close utility-only datasets that have not been accessed for 10 minutes proactively. When approaching DSMAX or DSMAX is reached, Db2 will prioritize the closure of utility-only datasets over those datasets that have been accessed by applications. Two new counters QTPCGBP and QTPCUT are created for the IFCID 2 trace records. QTPCGBP - Number of infrequently accessed data sets that are physically closed. A data set is considered to be infrequently accessed when it has not been accessed for the number of minutes that is specified by system parameter PCLOSET. Db2 physically closes the infrequently accessed data set that is defined with the CLOSE YES option when the following conditions occurred in a data sharing system: o A single member with R/W interest and any number members with read-only interest exist. o All members have read-only interest and the data set has been GBP-dependent since the time it was physically opened. QTPCUT - Number of utility-access-only data sets that are physically closed. Please refer to ++HOLD DOC change for more information. ×**** PE21/01/11 FIX IN ERROR. SEE APAR PH33238 FOR DESCRIPTION
APAR Information
APAR number
PH27493
Reported component name
DB2 OS/390 & Z/
Reported component ID
5740XYR00
Reported release
C10
Status
CLOSED UR1
PE
NoPE
HIPER
NoHIPER
Special Attention
NoSpecatt / Xsystem
Submitted date
2020-07-15
Closed date
2020-09-24
Last modified date
2021-02-11
APAR is sysrouted FROM one or more of the following:
APAR is sysrouted TO one or more of the following:
UI71764
Modules/Macros
DSNTXSTB DSNB1PCP DSNB1DCM DSNB1PFT DSNB1OPP DSNDQTST DSNB1DRN DSNB1DS1 DSNB1CPP DSNB5PCI
Fix information
Fixed component name
DB2 OS/390 & Z/
Fixed component ID
5740XYR00
Applicable component levels
RC10 PSY UI71764
UP20/10/02 P F010
Fix is available
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[{"Business Unit":{"code":"BU054","label":"Systems w\/TPS"},"Product":{"code":"SG19M","label":"APARs - z\/OS environment"},"Platform":[{"code":"PF054","label":"z\/OS"}],"Version":"12.0"}]
Document Information
Modified date:
12 February 2021