Subject: Re: Question re some improvements in NetBSD 1.6
From: Ignatios Souvatzis <email@example.com>
Date: 06/28/2002 11:31:38
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[I'm not fully sure, who wrote what, as the > > where inconsistent. I
reformatted as if the last quoted paragraph was by Iggy Drougge. Sorry
if this is wrong.]
On Fri, Jun 28, 2002 at 01:38:49AM -0400, Thomas Mueller wrote:
> "Iggy Drougge" <firstname.lastname@example.org> responded:
> > MOs are usually available in both plain 2048 and 512 byte block sizes. =
> > Fujitsu an exception?
> >From what they tell me, the newer MOs have sector size =3D 2048 bytes. =
> > MOs had sector size =3D 512 bytes. I think disk access is much faster =
> > the larger sector size. Does anybody make MO drives and disks besides
> > Fujitsu?
It's not a matter of old vs. new MOs. There are several technical details.
1. as I already wrote in a different message, 90mm MOs with 128, 230 and 540
MB are 512 bytes/sector only. 90mm MOs with 640MB, 1.3GB and 2.3GB are
2048 bytes/sector only.
2. higher capacity disks tend to be faster, because there is more capacity
per revolution, and more per seek operation, reachable. This is true at=20
least for sequential access.
3. Original MO technology needed 2 (3 with verify) revolutions to write:
the first to erase a track, the 2nd to write the 1 bits.=20
Some of the 540MB and higher capacity media are LIMDOW  media, and some
of the 540 MB and higher capacity drives operate in LIMDOW mode with
The result is that with this combination, you only need one revolution for
writing without verify.
 Light Intensity Modulated Direct Over-Write. Some media dealers=20
only mention "direct overwrite".
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