CPPAGTHR parameter: Difference between revisions

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current checkpoint stream, a checkpoint is immediately forced.</p>
current checkpoint stream, a checkpoint is immediately forced.</p>


<p>The default for CPPAGTHR is 0, meaning that it is not in use.
<p>The default for CPPAGTHR is 0, meaning that it is not in use.</p>
Effective with V8.0, if CPPAGTHR is unset and subtransaction checkpoints are enabled,
<p>Effective with V8.0, if CPPAGTHR is unset and subtransaction checkpoints are enabled,
CPPAGTHR will be set to a sliding scale from 50-90% of the smallest CHKPOINT/CHKPNTS primary extent size.</p>
CPPAGTHR will be set to a sliding scale from 50-90% of the smallest CHKPOINT/CHKPNTS primary extent size.</p>


[[Category:Parameters]]
[[Category:Parameters]]
[[Category:System parameters]]
[[Category:System parameters]]

Latest revision as of 19:33, 20 May 2026

Page write threshold for checkpoints

Summary

Default value
0 (Sliding scale in V8.0 with subtransaction checkpoints enabled)
Parameter type
System
Where set
System manager
Related products
All
Introduced
Model 204 version 7.9

Description

CheckPoint PAGe THReshold.

The new fullword CPPAGTHR parameter can be set to force a checkpoint when the number of pages written to the current stream hits the threshold.

If the threshold is small and it's hit while the checkpoint PST is writing out subtran checkpoint data, the threshold is ignored. If the checkpoint fails (must be non-subtran) it is not retried.

If the parameter is reset below the number of pages written to the current checkpoint stream, a checkpoint is immediately forced.

The default for CPPAGTHR is 0, meaning that it is not in use.

Effective with V8.0, if CPPAGTHR is unset and subtransaction checkpoints are enabled, CPPAGTHR will be set to a sliding scale from 50-90% of the smallest CHKPOINT/CHKPNTS primary extent size.