DB2 Version 9.7 for Linux, UNIX, and Windows

unread_prefetch_pages - Unread prefetch pages monitor element

Indicates the number of pages that the prefetcher read in that were never used.

Table 1. Table Function Monitoring Information
Table Function Monitor Element Collection Command and Level
MON_GET_BUFFERPOOL table function - Get buffer pool metrics DATA OBJECT METRICS BASE
MON_GET_TABLESPACE table function - Get table space metrics DATA OBJECT METRICS BASE
Table 2. Snapshot Monitoring Information
Snapshot Level Logical Data Grouping Monitor Switch
Database dbase Buffer Pool
Table Space tablespace Buffer Pool
Buffer Pool bufferpool Buffer Pool
Application appl Buffer Pool
For snapshot monitoring, this counter can be reset.
Table 3. Event Monitoring Information
Event Type Logical Data Grouping Monitor Switch
Database event_db -
Tablespaces event_tablespace -
Connection event_conn -

Usage

If this number is high, prefetchers are causing unnecessary I/O by reading pages into the buffer pool that will not be used.

Parent topic: Database system monitor elements