Subject: Re: mirroring for more than two disks?
To: NetBSD User's Discussion List <netbsd-users@NetBSD.ORG>
From: Greg A. Woods <woods@weird.com>
List: netbsd-users
Date: 11/25/2004 16:28:14
[ On Wednesday, November 24, 2004 at 15:43:24 (+1100), Luke Mewburn wrote: ]
> Subject: Re: mirroring for more than two disks?
>
> RAID10 is a RAID0 stripe of RAID1 mirrors:
>     -	with 4 disks, you have a stripe of two mirrors
>     -	with 6 disks, you have a stripe of three mirrors
>     	(etc)
> 
> There's no specific requirement to mirror with >2 disks
> per stripe component.

I haven't finished all my experiments comparing CCD with RAIDframe
RAID-0 but my initial impressions are that CCD is both faster and easier
on the overall system w.r.t. memory use and CPU cyles resource usage.

However I have not yet tried a CCD sripe of RAIDframe RAID-1 mirrors.

I think that such a configuration may give the best of both worlds (the
integrity management features of RAIDframe in exactly the place(s) where
they are needed, combined with the low costs and speed of CCD in the
place where integrity management isn't really needed).

Has anyone else tried this combination yet?

-- 
						Greg A. Woods

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