Subject: Re: proposal for non-512 bytes/sector block device
To: None <gibbs@plutotech.com>
From: Matthew Jacob <mjacob@feral.com>
List: tech-kern
Date: 06/26/1997 09:09:17
>From gibbs@plutotech.com Thu Jun 26 08:50:26 1997
>
>>Tape devices are a different story- but they are handled differently
>>anyhow. I can't think of a set of commonly available devices that
>>would make or break the notion of having systemwide variable sector
>>size support. From a formal point of view, this does have appeal,
>>but from a practical engineering point of view I'm not sure that the
>>amount of breakage and turmoil is worth it.
>
>Remeber that not all devices want to work with convenient, multiple
>of DEV_BSIZE, chunks of data. Audio CDs come to mind and the worm
>driver in FreeBSD currently goes through some rather ugly contorsions
>in order to allow you to write 2352 bytes at a time. I have no
>idea what the DVD formats look like, but I would expect that more
>problems like this one will crop up with future devices.
>
Oh, absolutely there are devices that take Mode2 amounts or don't
have DEV_BSIZE chunks- but my point here is that until they become
even a relatively common exception I don't see the need for major
rearchitecting of Unix.