Veritas Storage Foundation™ for Oracle 5.0.1 Administrator's Guide

following steps more than once to determine the best possible candidates for
Cached Quick I/O.
Before determining candidate files for Quick I/O, make sure the following
conditions have been met:
■ You must enable Cached Quick I/O for the file systems.
See “Enabling Cached Quick I/O on a file system” on page 103.
Prerequisites
■ See the qiostat (1M) manual page for more information.Usage notes
Collecting I/O statistics
Once you have enabled Cached Quick I/O on a file system, you need to collect
statistics to determine and designate the files that can best take advantage of its
benefits.
To collect statistics needed to determine files that benefit from Cached Quick I/O
1
Reset the qiostat counters by entering:
$ /opt/VRTS/bin/qiostat -r /mount_point/filenames
2
Run the database under full normal load and through a complete cycle (24 to
48 hours in most cases) to determine your system I/O patterns and database
traffic in different usage categories (for example, OLTP, reports, and backups)
at different times of the day.
3
While the database is running, run qiostat -l to report the caching statistics
as follows:
$ /opt/VRTS/bin/qiostat -l /mount_point/filenames
or, use the -i option to see statistic reports at specified intervals:
$ /opt/VRTS/bin/qiostat -i n /mount_point/filenames
where n is time in seconds
For example:
To collect I/O statistics from all database files on file system /db01:
$ /opt/VRTS/bin/qiostat -l /db01/*.dbf
Using Veritas Cached Quick I/O
Determining candidates for Cached Quick I/O
108