Re: RAID

[lsorense@csclub.uwaterloo.ca (Lennart Sorensen)]

On Thu, Nov 10, 2005 at 11:03:30AM -0800, lordSauron wrote:
> So, if I can get a decent RAID 0 PCI card that'd be better than using
> my CPU time on it, correct?  Even if I'm a cheap person and get one of
> the worst cards there is, would that be faster or slower than software
> RAID?  Particularly Linux's software RAID.

RAID0 doesn't require any calculations other than which block to read
from (nor does RAID1), so software and hardware should be the same speed
really.  Booting from raid0 would probably be tricky.  If you make /boot
be a plain simple partition on the first disk, and install the boot
loader to the MBR of the first disk, then you can use raid0 for the rest
of your stuff across the remaining space without any boot problems.

RAID3/4/5/6 is where XOR calculations come in, and hardware raid might
be worth while.  Hardware raid is also nice for making booting simple
since the whole raid appears as one disk to the OS.  Fake raid does that
too of course.

Len Sorensen