Re: RAID and Oracle

Bruce has made a _VERY_ important point here.

>
> DBAs need to be able to pick and choose the type of RAID (if any) required
> for each database component. Why put the TEMP tablespace (high write and
> read but not critical tablespace) on a slow but very reliable device?
>

Lots of sites seem to discuss their disk issues along the lines of:

        'should we use RAID 0+1 or RAID 5'

Different parts of the database can be on different versions of RAID, or even on the same type of RAID with (say) different stripe sizes.

It is perfectly reasonable to have:

	TEMP tablespaces (both of them) on non-RAID
	REDO on mirrored non-striped
	Indexes on RAID5 with small stripe size
	Some tables on RAID5 with small stripe size
	Some tables on RAID0+1 with large stripe size
		etc.

The possible variations are numerous, although as a general rule I personally tend to compromise and avoid having more than 4 or 5 variations in the system on the basis of KISS.

---
Jonathan Lewis
ora_mail_at_jlcomp.demon.co.uk