balon@hpcupt1.cup.hp.com (Tom Balon) (04/24/91)
How do different versions of unix deal with new ZBR (Zone Bit
Recording)) style disk drives. These drives are divided into
several zones with a different number of sectors/track in each
zone.
As I understand it, the unix file system uses the track size,
block/frag size, and information from the super block ( rotdly
for example ) in order to optimally allocate the next disk block.
This may not work well with ZBR. For example, say we have a
disk with 1 to n zones. We build a 8K/1K file system on the disk.
In zone 1, the track size is 32K so we have 4 8K blocks per track,
in zone n, the track size is 24K so we have only 3 8k blocks per
track. Under these conditions, the old algorithm breaks down.
- Tom
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***********************************************************************alan@ukpoit.co.uk (Alan Barclay) (05/03/91)
In article <67930001@hpcupt1.cup.hp.com> balon@hpcupt1.cup.hp.com (Tom Balon) writes: > > > > How do different versions of unix deal with new ZBR (Zone Bit > Recording)) style disk drives. These drives are divided into > several zones with a different number of sectors/track in each > zone. > For what I've worked out it the controller for these drives do sector translation, so the OS sees a disk with normal fixed sectors per track. -- Alan Barclay iT | E-mail : alan@ukpoit.uucp Barker Lane | BANG-STYLE : .....!ukc!ukpoit!alan CHESTERFIELD S40 1DY | VOICE : +44 246 214241