Subject: Re: SCSI disks & controllers
To: Douglas K. Rand <>
From: Michael L. VanLoon -- Iowa State University <>
List: current-users
Date: 02/26/1994 15:23:02
>Enough people have been telling me to dump my IDE drives/controllers
>and go to SCSI for NetBSD, so OK, here I go. I'll get rid of my 3 IDE
>disks (2x200 Mb 1x540 Mb) and the caching IDE controller and get all

Good for you. :-)

>So, which controller to get? I've got a local bus mother board and I'd
>like to take advantage of it. From what I hear on the list, it sounds
>like the Ultrastore 34F and the Bus Logic 445S are the controllers of
>choice. Anybody have any suggestions on these, or others. They are
>priced with in about $10-$20 of each other. (34f: $242  445s: $249)

I really like my BusLogic 747s.  I'd recommend the BusLogic, but I've
never used an Ultrastor, so my opinion is biased.  BusLogic does have
great tech. support from my experience.

>Also, which drives (if any) do people suggest?

Probably anything large and newish will work great.

>Or should I be looking at two separate drives? 

The advantage to two drives is you can set up true interleaved paging
with SCSI.  This should make swapping operations a bit faster.  IDE
doesn't (normally) allow multiple drives to be seeking simultaneously,
unlike SCSI were all devices operate independently and simultaneously.
Plus the IDE (wd.c) driver doesn't do DMA since most IDE drives don't
support DMA, meaning the processor has to spend its time moving all
the data instead of letting the controller do the work (unlike the
intelligent SCSI controllers mentioned which do DMA by default).
(Someone correct me if I'm wrong here.)

The disadvantage to double drives is that it's probably a bit more
expensive this way, and of course, the extra work of setting up lots
more partitions.

>PS: I like this method of fixing wd.c! ;-) 

Was the best fix I found. :-)

P.S. If you get the BusLogic card and my updated bt742a.c driver
hasn't been incorporated into current yet, drop me a line and I'll
send it directly to you.

    Michael L. VanLoon  --  --  gg.mlv@isumvs.bitnet
 Iowa State University of Science and Technology -- The way cool place to be!
   Project Vincent Systems Staff, Iowa State University Computation Center