On 19/02, Allen S. Rout wrote:
> >> On Thu, 19 Feb 2009 16:27:29 +0100, km <km AT GROGG DOT ORG> said:
>
>
> > RAID5 will give you the maximum amount of IOPS for the DB with disk
> > redundancy, though 4 disks is on the low side.
>
> > TSM mirroring doesnt help performance when doing expiration or
> > reclamation anyway which is what you want to optimize the DB for.
>
>
> This debate has raged on and on over years.  IOPS vs. recoverability,
> mirroring at TSM level, AIX level, hardware level..  There are well
> established camps with their advocates and thought leaders.  Look
> through the archives.  We re-debate the topic once or twice a year.
>
>
> but the former things have passed away, and there is no more sea.
>
> As has already been said here: we need to forget these things, and
> start asking the DB2 folks how they accomplish performance and
> stability goals.  We don't know what we're doing any more.  We need to
> get used to it, and re-learn.
>
>
>
> - Allen S. Rout
> - Whiny.

True dat!

As with everything performance related, the advice given is a rule of thumb
from where to start. Everybody has different goals. Testing yourself with
your own goals in mind is what will give you your truth. YMMV and at
last with DB2 alot of the serialized log write penalty will disappear.

Though I believe this question was about < 6.x (since it hasnt been
released yet) and only about maximising performance for the DB.

-km