Re: NT Oracle database with RAID-5 hardware controller - Is it good?

Hi,

At our company, we've been in the process of setting up an Oracle 8.0.4 data warehouse on a SUN server running Solaris 2.6, attached to a very large disk array.

After numerous talks with SUN, the SUN Tech VAR installers, and Oracle on this very issue of RAID5-vs-Other Setups, I have come to use a pretty simple set of formula-like reasonings for my DB's:

1. If the DB is *mostly* READ-centric, and very large, then use RAID-5.
2. If the DB is *mostly* WRITE-centric, then use 0+1 mirroring, and as much as possible try to segment the DB accross multiple drives. (Although we're using mostly 9 and 18 Gig SCSI-III drives now, that allows for alot of data per drive.)
3. When mirroring drives in 0+1, if at all possible, try to mirror *accross* drive controllers. Meaning, Drive1 on Controller1, mirroring Drive2 on Controller2. This is not *really* necessary, except that it adds that extra level of security for the completely paranoid about "what if the whole drive controller fails?". (This is still a questionable idea to me, and I'm researching it's actual practical value.)
4. Separate Indexes and Logs and Rollback segments from the actual data tablespace itself. I always try and put my data in a tablespace that spans ONE set of drives on, and my indexes and other control files on a completely different set of drives.

That's about it.

This simple set of principles helps me make *lots* hardware and DB layout decisions.

If anyone has a rule to add to my list, I always appreciate the input. *S*

Regards,

James Arvigo
Developer / DBA
Thrifty Call, Inc.
San Marcos, TX
jamesa_at_NOSPAM.thriftycall.com
(just remove the NOSPAM)

fantail2 wrote:

> I just heard that if you install an Oracle database on a COMPAQ ProLiant
> with a RAID-5 disk controller, the performance of the database is greatly
> reduced.
>
> Can someone can explain to me why?
>
> Thanks!
Received on Wed Jul 29 1998 - 00:29:17 CDT