Date: Sun, 6 Aug 2000 18:51:40 +0200 From: Francesco Casadei <fcasadei@inwind.it> To: Greg Lehey <grog@lemis.com> Cc: Francesco Casadei <fcasadei@inwind.it>, freebsd-questions mailing list <freebsd-questions@FreeBSD.ORG> Subject: Re: LS120 drive has a strange behaviour with 1.44MB floppy Message-ID: <20000806185140.A563@casimirhost.kasby> In-Reply-To: <20000806122756.C69570@wantadilla.lemis.com>; from grog@lemis.com on Sun, Aug 06, 2000 at 12:27:56PM %2B0930 References: <20000805184339.A426@casimirhost.kasby> <20000806122756.C69570@wantadilla.lemis.com>
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On Sun, Aug 06, 2000 at 12:27:56PM +0930, Greg Lehey wrote:
[snip]
> Try this:
>
> dd if=/cdrom/freebsd/floppies/kern.flp of=/dev/rafd0 bs=36b
>
> I would expect the transfer rate to increase to about 30 kB/s and the
> time to be about 50 seconds. Is that correct?
>
> The background here is that the first form writes one sector at a
> time. For whatever reason, by the time you issue the next write
> command, the write head has already passed the sector, and you have to
> wait a complete revolution. That should make six sectors a second, or
> about 3 kB/s. I'm not sure why it's even slower than that, but
> possibly retries or head change problems could influence it.
>
> Greg
> --
[snip]
>
> end of the original message
root> dd if=/cdr/freebsd/floppies/kern.flp of=/dev/rafd0 bs=36b
80+0 records in
80+0 records out
1474560 bytes transferred in 81.922018 secs (18000 bytes/sec)
This is 9 times faster than using the default block size. But the
LS-120 SuperDisk drive is supposed to be 500% faster than standard
floppy drives with 120MB diskettes and three times faster
(reading/writing) than an ordinary floppy drive with 1.44 MB
diskettes!
There's another thing that I don't understand: what does "Resource
temporarily unavailable" mean?
root> dd if=/dev/zero of=/dev/rafd0 count=2
2+0 records in
2+0 records out
1024 bytes transferred in 0.499711 secs (2049 bytes/sec)
root> disklabel /dev/rafd0 | disklabel -B -R -r rafd0 /dev/stdin
disklabel: /dev/rafd0c: Resource temporarily unavailable
root> disklabel /dev/rafd0 | disklabel -B -R -r rafd0 /dev/stdin
disklabel: /dev/rafd0c: Resource temporarily unavailable
root> disklabel /dev/rafd0 | disklabel -B -R -r rafd0 /dev/stdin
root> newfs /dev/rafd0c
Warning: 1216 sector(s) in last cylinder unallocated
/dev/rafd0c: 2880 sectors in 1 cylinders of 1 tracks, 4096 sectors
1.4MB in 1 cyl groups (16 c/g, 32.00MB/g, 384 i/g)
super-block backups (for fsck -b #) at:
32
I'd like to know if this behaviour should be considered correct
or I have a configuration problem or there's a problem in the "new"
ata driver.
Francesco Casadei
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