Re: SATA, RAID, A8N-E, 3800+ help

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

On Sat, Jan 28, 2006 at 01:10:10PM -0500, Anthony DeRobertis wrote:
> The OP said any driver, and I pointed out that isn't true. Trying to
> have users tell the difference between software raid drivers and
> hardware raid drivers is, I think, harder than just having them tell
> software vs. hardware raid controllers apart. After all, the latter can
> be done with a high confidence by looking at the price tag.
> 
> Linux software raid has a lot of advantages like being able to configure
> on a per-partition, not per-disk, basis. Many true hardware raids can't
> even do that.

I think most of them can do volumes on a raid, which is essentially
partitions.  They show up as seperate drives then.  Of course you can
also partition the raid device since it is just a disk to the OS.

> However, I haven't actually seen benchmarks showing its faster. I'm not
> sure how you'd benchmark it, either... You'd have a lot of
> windows-vs-linux differences to filter out somehow.

I was told by a 3ware dealer that many of their users run linux software
raid on their 12 port cards, because they find with a modern cpu linux
software raid beats the 3ware hardware raid chip.  So they use it as a
single card 12 driver sata controller instead.

I certainly know in the past I got a drop in performance when going from
software raid1 to an ibm serveraid 4m doing raid1.  I was surprised and
rather disappointed in that.  The hardware raid was easier to manage
though.

Len Sorensen