Performance of WD1006 vs. Adaptek 2372 RLL comtrollers

[davidsen at sungod.crd.ge.com]

I recently replaced an Adaptek 2372 RLL controller with a WD1006VSR2.
Under DOS the read performance was about 600KB (Core test) for both,
while under Xenix the Adaptek showed about 120kb while the WD gave
320kb. The Adaptek had a habbit of forgetting the disk type of the 2nd
hard disk when powered down. Several people told me they had seen this.

Summary: the WD does its track buffering in hardware and doesn't depend
on the BIOS to do part of the work. It seems to have fewer quirks in
operation. The WD is a *pain* when doing low level format, because it
stops on each error and asks if you want to mark the error. This leaves
you sitting there. It's surface test seems better than the Adaptek,
because Xenix badtrk didn't find any new bad tracks after the WD
checked. I've been running a week and no new bad tracks yet. Under Xenix
the backups ran peak 5MB/min (limited by the tape) with WD, average
4.02MB/min including time to change tapes. The Adaptek runs about
1MB/min because it can't keep the tape streaming.

Hope this is of use. The Adaptek is still a fine controller for someone
(a) running DOS, and (b) running one HD. I will probably sell off the
Adaptek soon and I don't feel that anyone will be cheated buying it, but
I *will* warn the buyer.
	bill davidsen		(davidsen at crdos1.crd.GE.COM)
  {uunet | philabs}!crdgw1!crdos1!davidsen
"Stupidity, like virtue, is its own reward" -me