Skip to Content

DBPrefetchEffRatio (DB2UDB_BUFFERPOOL)

Indicates the ratio of asynchronous data reads to synchronous data reads. This parameter can be used to determine the correct setting for the num_ioservers configuration parameter. 

Asynchronous reads performed by Database Manager pre-fetchers are responsible for paging-in data from the disk to the buffer pool.  Prefetching can only be performed on data pages.  Therefore, prefetching will not improve the index page hit ratio.

The BUFFERPOOL DB2 Monitor Switch must be set ON to make this parameter active and collect data.

Parameter value calculation

Buffer Pool Async Data Reads / (Buffer Pool Data Physical Reads - Buffer Pool Async Data Reads)

Default parameter attributes

Attribute

Default value

Application class

DB2UDB_BUFFERPOOL

Command type

not applicable

Platform

All

Active at installation

yes

Parameter type

Consumer

Scheduling (poll time)

not applicable

Icon style

Graph

Alarm 1 range

not applicable

Alarm 2 range

not applicable

Border range

not applicable

Unit

Ratio

Annotated?

No

Value set by

CollBufferpool

 

Tip: For faster searching, add an asterisk to the end of your partial query. Example: cert*

BMC PATROL for DB2 Universal Database 9.0