A fix is available
APAR status
Closed as program error.
Error description
The customer is running a REORG utility on a partitioned tablespace with 731 partitions an 8 indexes . When using Db2Sort as sort product the job takes longer elapsed time and using more CPU than the case when using DFSort. This happens because in the Db2sort case there are less parallel tasks started by the Reorg utility. This happens because of db2sort memory requirement calculation below the 16Mb line that is no longer necessary and can be removed. This will enable more below the line virtual storage to be exploited by the utility job, this increasing the degree of parallelism.
Local fix
Problem summary
**************************************************************** * USERS AFFECTED: All Db2 11 for z/OS and Db2 12 for z/OS * * users of REORG TABLESPACE utility with * * Db2 Sort * **************************************************************** * PROBLEM DESCRIPTION: Improve below the line virtual memory * * calculation for subtasking parallelism * * of REORG TABLESPACE with Db2 Sort * **************************************************************** * RECOMMENDATION: Apply corrective PTF when available * **************************************************************** This APAR improves the below the line virtual memory calculation for REORG TABLESPACE execution using Db2 Sort. In particular, the degree of parallelism calculation for Db2 Sort in REORG TABLESPACE eliminated an unnecessary cushion previously reserved for storage fragmentation. This enables maximal use of the below the line virtual memory and has a potential to enable a higher degree of sort parallelism in REORG compared to before.
Problem conclusion
Code has been modified to improve the below the line virtual memory calculation for REORG TABLESPACE execution with Db2 Sort.
Temporary fix
Comments
APAR Information
APAR number
PH13562
Reported component name
DB2 OS/390 & Z/
Reported component ID
5740XYR00
Reported release
B10
Status
CLOSED PER
PE
NoPE
HIPER
NoHIPER
Special Attention
NoSpecatt / Xsystem
Submitted date
2019-06-19
Closed date
2019-07-30
Last modified date
2019-09-01
APAR is sysrouted FROM one or more of the following:
APAR is sysrouted TO one or more of the following:
UI64496 UI64499
Modules/Macros
DSNURPCT
Fix information
Fixed component name
DB2 OS/390 & Z/
Fixed component ID
5740XYR00
Applicable component levels
Fix is available
Select the PTF appropriate for your component level. You will be required to sign in. Distribution on physical media is not available in all countries.
[{"Business Unit":{"code":"BU059","label":"IBM Software w\/o TPS"},"Product":{"code":"SSEPEK","label":"Db2 for z\/OS"},"Component":"","ARM Category":[],"Platform":[{"code":"PF025","label":"Platform Independent"}],"Version":"11.0","Edition":"","Line of Business":{"code":"LOB10","label":"Data and AI"}},{"Business Unit":{"code":"BU054","label":"Systems w\/TPS"},"Product":{"code":"SG19M","label":"APARs - z\/OS environment"},"Component":"","ARM Category":[],"Platform":[{"code":"PF025","label":"Platform Independent"}],"Version":"11.0","Edition":"","Line of Business":{"code":"","label":""}}]
Document Information
Modified date:
01 September 2019