Subject: Re: Four Drive RAID-5 on RAIDFrame Considered Harmful...
To: Robert P. Thille <list-netbsd-tech-perform@rangat.org>
From: Thor Lancelot Simon <tls@rek.tjls.com>
List: tech-perform
Date: 10/09/2007 21:53:01
On Tue, Oct 09, 2007 at 04:59:58PM -0700, Robert P. Thille wrote:
>
> I tracked it down to the problem that 2 and 3 are relatively prime :-)
> Given 4 drives in a RAID-5 setup, you get 3 data blocks per raid stripe,
> but the filesystem block size Must be a power of 2, so you always have
> to write at least one partial stripe.
No. Examine the "maxcontig" FFS parameter.