On Thu, 21 Nov 2002, Bjoern Metzdorf wrote:
> > In fact, the linux kernel supports >2 drives in a mirror. Useful for a
> > mostly read database that needs to handle lots of concurrent users.
>
> Good to know.
>
> What do you think is faster: 3 drives in raid 1 or 3 drives in raid 5?
Generally RAID 5. RAID 1 is only faster if you are doing a lot of
parellel reads. I.e. you have something like 10 agents reading at the
same time. RAID 5 also works better under parallel load than a single
drive.
The fastest of course, is multidrive RAID0. But there's no redundancy.
Oddly, my testing doesn't show any appreciable performance increase in
linux by layering RAID5 or 1 over RAID0 or vice versa, something that
is usually faster under most setups.