Re: Oracle Performance on RAID 5

Hi

Yes I did note the poor write performance of RAID5 for writes. I am more concerned about the read performance. From what I read you should have very good read performance unless your stripe size is too small.

I know that keeping my redo logs, Temp tablespace or any other write intensive areas off the RAID 5 will improve the performance. Still, I will probably put it all on RAID5 and have a hot standby drive in the array. I know it will slow it down but this is a Dispatch system for Ambulance/Fire and if it is down there could be a drop in the response time for our Ambulance and Fire crews. So this System MUST be up.

What concerns me is Vendor claims that I will suffer a performance hit on reads. All the literature I've read indicates that this is not true. My experience on RAID5 has been good. No read performance degradation in my experience. I'm just asking if anyone has had a drop on read performance for reads.

l8r
Robert Hart

MotoX wrote in message
<898170190.23434.0.nnrp-09.c2de712e_at_news.demon.co.uk>...
>Mirrored disks can in fact slow 'writes' down, as the data has to be
sync'ed
>between both drives. I'd suggest looking at striping and/or RAW devices for
>improved write performance for TEMP. Obviously look at mirroring if you
want
>FT as well. Oh, and test a number of configurations, as all databases and
>hardware/software mixes are different.
>
>One point worth noting about your TEMP tablespace is that you can always
>drop it and recreate it if you hit problems, unlike all the other data
files
>and logs, so mirroring it may not be necessary. It all depends on your
>up-time requirements.
>
>Once last point: note what was said about the poor write performance of
>RAID5 on writes (i.e. not good for TEMP and redo - or bulk updates, if you
>do a lot of that).
>
>MotoX.
>
>
Received on Thu Jun 18 1998 - 09:09:54 CDT