Re: HELP: RAID-5 Killing Performance

Switch on timed_statistics before you
do anything else. Then check v$system_event to find out where you lose most time. Also check volume and average write times for data, temp, rbs, and redo before worrying about whether you should change the configuration.

It is probably not sensible to archive direct to tape - (a) it's hard to manage changing the tapes in a timely fashion, (b) writing to tape is usually much slower than writing the redo log so you would end up tape-bound and (c) tapes are more error prone than discs.

--

Jonathan Lewis
Yet another Oracle-related web site: http://www.jlcomp.demon.co.uk

In2Home User wrote in message
<937333485.18113.0.pink.d4e11496_at_news.in2home.co.uk>...
>We're running Oracle 8.0.5 on Solaris 2.6.
>Our database server is a Sun UltraSparc I 333MHz with 1GB of RAM.
>We have several disks, a RAID-5 array, and a local tape device.
>
>My DBA is utilizing the disks in the following manner:
>
>disk1 - os
>disk2 - home
>disk3 (mirrored) - archived redo logs
>disk4 (RAID-5) - control file, system, temp, oracle software
>disk5 (RAID-5) - control file, rbs, redo logs
>disk6 (RAID-5) - control file, tools, users, redo logs
>
>My largest concern is that having the redo logs on RAID-5 has
>got to be killing my performance. Ideally, they should be on a
>dedicated set of mirrored drives (then again, ideally I should have
>22 separate disks, yeah). However, my DBA feels that its more
>important to have the archive logs on the dedicated mirrored disks.
>
>Anyone care to share their opinion as to how we might make better
>use of the above hardware setup? Would it make sense to write archive
>logs directly to tape and move the redo logs to the mirrored disks?
Received on Tue Sep 14 1999 - 13:48:03 CDT