[Discuss] SW vs HW raid (was raid controller drivers)

[jabr at blu.org (John Abreau)]

I think I see it now. I said I prefer software raid over hardware raid, and
your response is that zfs software raid is preferable to hardware raid.

So basically, you're disagreeing with the same arguments that I was
disagreeing with, and I misread it as you disagreeing with my argument.


On Fri, Sep 26, 2014 at 10:11 AM, Edward Ned Harvey (blu) <blu at nedharvey.com
> wrote:

> > From: jabr at gapps.blu.org [mailto:jabr at gapps.blu.org] On Behalf Of John
> > Abreau
> >
> > I don't see how ZFS is a counterexample. I'm aware of ZFS as a software
> > component of the OS, but I've never even heard of ZFS being baked into
> the
> > disk controller below the level of the OS.
> >
> > An argument about ZFS as an alternative to both hardware and software
> > RAID would be completely orthogonal to an argument about the relative
> > merits of hardware vs software RAID. It wouldn't be a counterexample;
> > instead, it would be an entirely different discussion.
>
> ZFS does software raid, and because it has intimate knowledge of the
> filesystem (not just doing raid at the block level) it is able to do
> performance optimizations that cannot be done with hardware raid (having
> only knowledge of the block level).  So ZFS software raid outperforms
> hardware raid.
>
> Did that make it clearer?
>



-- 
John Abreau / Executive Director, Boston Linux & Unix
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