RE: Journal performance problems

["Andy Nolen-Parkhouse" <aparkhouse@xxxxxxxxx>]

Oliver,

Replies inline:

Regards,
Andy Nolen-Parkhouse

> On Behalf Of ouuch@xxxxxxxxxxx
> Subject: RE: Journal performance problems
> 
> Well, during some heavy-duty batchjobs, ASP2 disk goes up to 70-80% for
> some
> time. Could it be better to RAID the drives in ASP2? I currently have 2
> drives to be
> built in on saturday and am trying to decide if they go to ASP2 or
> ASP1.
> Would 4 drives in a RAID-config be better than 2 drives mirrored?

70-80%!  Ouch!  If those numbers are present for extended times, then the
poor thing is overwhelmed.

Yes, four arms in RAID would provide more throughput than in a mirrored
configuration.  Particularly since you are concerned with writes, not
reads.

> At busy times, one of the journals uses 3-4 journal receivers inside 60
> minutes, each
> receiver at 1GB size.

The largest cache available (which is not compatible for your 820) is on
the #2757 with 235 MB.  Your #2748 has a 26 MB write cache (I don't
recognize any other disk controllers in the feature codes you listed).

> IBM has a licensed programm - Journal cache. Could this be helpful for
> us?

I'm not familiar with it.

> Regards,
> 
> Oliver
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