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Buffer Pool Threshold Cleaners Triggered


Snapshot Information Level
Database

API Structure(s)
sqlm_dbase

Monitor Group
Buffer Pool

Resettable

Yes

 

Event Information Level
Database

API Structure(s)
sqlm_db_event

  

API Element Name
Element Type

pool_drty_pg_thrsh_clns
counter

 

Description:  The number of times a page cleaner was invoked because a buffer pool had reached the dirty page threshold criterion for the database.

Usage:  The threshold is set by the chngpgs_thresh configuration parameter. It is a percentage applied to the buffer pool size. When the number of dirty pages in the pool exceeds this value, the cleaners are triggered.

If this value is set too low, pages might be written out too early, requiring them to be read back in. If set too high, then too many pages may accumulate, requiring users to write out pages synchronously. See the Administration Guide for more information.

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