MSRES parameter

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Maximum SREs per file in RETBL

Summary

Default value
0
Parameter type
System
Where set
On User 0's parameter line or reset by system manager
Related products
All
Introduced
Model 204 V5.1

Description

The MSRES parameter controls how entries are stored in the Record Enqueuing Table for transaction backout (TBO) pending updates. When MSRES is set to 0, TBO pending update entries are stored as record set entries. These may use less storage space in the Record Enqueuing Table.

If MSRES is set to a nonzero value, that value is the maximum number of TBO pending updates per file that will be stored as Single Record Entries (SREs). When a file requires more than MSRES SREs, all SREs are converted to record set entries.

A nonzero MSRES may require a larger Record Enqueueing Table, but the CPU cost of reading the entries may be reduced when they are SREs. The amount of additional space and the level of performance improvement are application dependent.