[rescue] Any Minneapolis area listers ?

Charles Shannon Hendrix shannon at widomaker.com
Wed Jan 10 13:15:20 CST 2007

Wed, 10 Jan 2007 @ 02:57 -0500, der Mouse said:

> If you're going for low price, why use "hardware" (usually really
> firmware) RAID at all?  Why not go with software RAID?

Software RAID puts all of the RAID overhead on the host.

If you have a good RAID controller, that overhead happens on the
controller instead, which offloads work from your host bus.

Just for example, mirroring:

If I write 10MB in reality my computer must write 20MB since it has to
do a write to each side of the mirror.

By contrast, if I'm using a RAID controller, the mirror RAID I/O happens
on that controller, so my host bus only has to do the 10MB.

Naturally to get the benefit of this the RAID controller needs to be
fast enough to handle the overhead without delaying your host, but some
fairly fast RAID controllers can be had for relatively low prices now.

shannon "AT" widomaker.com -- [4649 5920 4320 204e 4452 5420 5348 5920 4820
2056 2054 434d 2048 4d54 2045 204e 5259 4820 444e 0a53]

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