DB2 Version 9.7 for Linux, UNIX, and Windows

pool_async_write_time - Buffer pool asynchronous write time monitor element

The total elapsed time spent writing data or index pages from the buffer pool to disk by database manager page cleaners. This value is reported in milliseconds.

Table 1. Table Function Monitoring Information
Table Function	Monitor Element Collection 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

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	-

Usage

To calculate the elapsed time spent writing pages synchronously, use the following formula:

 pool_write_time - pool_async_write_time

You can also use this element to calculate the average asynchronous write time using the following formula:

 pool_async_write_time
  / (pool_async_data_writes 
    + pool_async_index_writes)

These calculations can be used to understand the I/O work being performed.