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Sysview for DB2 history file resizing considerations

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Article ID: 131649

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Updated On:

Products

Bind Analyzer for DB2 for z/OS SQL-Ease for DB2 for z/OS SYSVIEW Performance Management Option for DB2 for z/OS Plan Analyzer for DB2 for z/OS Subsystem Analyzer for DB2 for z/OS

Issue/Introduction

Due to the extreme thread history volume, the Sysview for DB2 history files are only providing a few minutes of data before they wrap. 
Is there information on how to calculate larger allocations for the history files to accommodate at least twenty-four hours worth of history?

Environment

IDB2 r19.  DB2 v11, v12

Resolution

The following link provides the calculation considerations:

https://techdocs.broadcom.com/us/en/ca-mainframe-software/database-management/ca-sysview-performance-management-option-for-db2/19-0/configuring/data-collector-dc/online-history/online-history-data-sets/empirical-estimation-of-history-data-set-sizes.html

Additional Information

In this specific case where the files wrapped within minutes, recommendation was made to initially increase the history files
to contain a couple of hours, and then run the calculation as described in the above link. 
From there, a more finite adjustment could be made.