ISC disk driver bug? (Was Disks Hang Under 2.0.2 SCSI add WD1006SRV2)

[Piercarlo Grandi]

In article <511092 at nstar.UUCP> larry at nstar.UUCP (Larry Snyder) writes:

   I'm no longer running the controller, like SCO - and am not having any 
   problems.  The 2372B might not be as fast - but it works.

With ESIX, I get bandwidth out of the 2372B that matches that
published for the WD1006. With caching disabled. BTW, the way to enable
caching with the ACB is jumper J2-5, if I remember correctly. I
run it disabled because it only helps really in the two following conditions:

	sequential reads from the block device

	reads from a filesystem that has been made with too small a gap

which are not my type of things, and slows down more than a
little on writes to the filesystem. Somebody observed that my
tests have been using too large a blocking factor (on purpose, I
wanted to see the maximum performance obtainable), and that read
ahead may be more useful with reads using smaller block sizes. I
seem to remember that I tried and this is not really true. Will
do some more experiments...

--
Piercarlo "Peter" Grandi           | ARPA: pcg%cs.aber.ac.uk at nsfnet-relay.ac.uk
Dept of CS, UCW Aberystwyth        | UUCP: ...!mcvax!ukc!aber-cs!pcg
Penglais, Aberystwyth SY23 3BZ, UK | INET: pcg at cs.aber.ac.uk