Re: Data Warehousing - RAID5 or RAID0-1

George.Brennan_at_warnermusic.com wrote:
>
> RAID 5 always requires 1 disk for parity information, well really it's
> distributed parity but the effect is the same. It requires a minimum of 3
> drives, hmm, come to think of it I don't know what the upper drive limit is.

Personally, I have found that if you go above 10 physical disks in a RAID 5 set, the rebuild time onto a hot spare becomes unacceptable. YMMV.

In practice, I would be very unlikely to use a set this big, because if you're storing that much data (in, say, a single tablespace) you'd be better off creating multiple physical volume groups and partitioning.

Cheers,

g

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