Subject: Re: Supporting sector size != DEV_BSIZE
To: Johan Danielsson <joda@pdc.kth.se>
From: Bill Studenmund <wrstuden@netbsd.org>
List: tech-kern
Date: 10/08/2001 05:25:02
On 9 Oct 2001, Johan Danielsson wrote:

> Bill Studenmund <wrstuden@netbsd.org> writes:
>
> > One thing I built into the wrstuden-dev-bsize branch was support for
> > non-power-of-two block sizes; I now think that's not needed.
>
> 520 byte sector disks are not that uncommon (used with many raid
> systems); we can of course choose to ignore this problem. Harder to
> ignore is the 2352 byte sectors of audio CD:s.

The problem (which is the reason I officially abandoned this branch) is
that with UBC, the primary data cache is the VM cache, which operates in
terms of VM pages (which I belive are 8k for most ports). 2352 byte
sectors don't fill 8k pages very well...

Take care,

Bill