Frank van Bortel wrote:
> Had not seen this whilst replying to the other.
>
> Of course I was talking about hardware RAID.
>
> And as right as you probably are, I have never seen
> hardware mirroring being substantially slower than
> single disks for writing. Note substantially is not
> the same as measurable; it can be measured, sure.
>
Any comparism between Single disk and SATA RAID
controllers (I know - not SCSI, but SCSI will
and should outperform SATA) shows:
- Access times on RAID1 are better than single disk
(http://tweakers.net/reviews/536/17)
- Most h/w RAID controllers show better write throughput
on RAID1 than on single disks; those that show decreased
performance do *not* show 33% decrease, but far less (15%)
(http://tweakers.net/reviews/536/19)
- In an average database environment, mixed IO, RAID1
outperforms single disks (http://tweakers.net/reviews/536/25)
- You want RAID5 with more than 3 disks - OT
--
Regards,
Frank van Bortel
Received on Mon Jun 13 2005 - 13:11:02 CDT
