Path: utzoo!attcan!uunet!seismo!dimacs.rutgers.edu!mips!swrinde!zaphod.mps.ohio-state.edu!samsung!umich!yale!cmcl2!panix!alexis
From: alexis@panix.uucp (Alexis Rosen)
Newsgroups: comp.periphs
Subject: Re: ESDI vs. SCSI for 486 Disks?
Keywords: ESDI SCSI Disk Controller
Message-ID: <1990Oct2.081744.6349@panix.uucp>
Date: 2 Oct 90 08:17:44 GMT
References: <9678@ur-cc.UUCP> <14174@netcom.UUCP>
Organization: PANIX - Public Access Unix Systems of NY
Lines: 41

In article <14174@netcom.UUCP> feustel@netcom.UUCP (David Feustel) writes:
>Get an IDE controller and hang two (conner) 200 meg drives on it.
>Each drive has its own 64k buffer and the transfer rate between drive
>and cpu is up to 4mbyte/sec. You then will have no problems running
>any software that expects an MFM controller since they have the same
>interface.

This is really bogus. The connors drives are 3.5" mechanisms. So their
transfer rate is really lousy compared to 5.25" disks. Seek's pretty good,
but not best. (Transfer's respectable for a 3.5"- it's not poorly-built.)

I can't tell you much about PC host adaptors, but if you want really fast:
1) Make sure you get two disks (or more) so you can share the load. Make
sure that, at the very least, swap is on a different drive than your most
commonly-used data files.
2) SCSI is unquestionably the interface of the future. For now? Well, it looks
pretty damn good. The best drive I know of in your range is the 400MB drive
from Imprimis (Seagate). But, you might well do better with two 170MB drives.
(These are all Wrens.) It really depends on your situation. If you really
want speed at a decent price, get two Wren Runners for a total of 600MB. They
can be had for about $1800 apiece or less. The 400 is about $2600- more
expensive, and a little slower than the Runners, since the 400 is a half-height
mechanism.
3) The Wren Runner has the fastest true average seek time of any mechanism I
know. They claim 10.7ms, I say 11-12 depending on the unit.
Of course, if you really have a need for speed, the new Imprimis Elites,
starting at 1.5GB, are incredible. Still hard to come by though.

Almost forgot- most of these Wrens have small caches. In general, you'd do
better by putting more memory in your unix box than by buffering the disk.
In particular, you can throw on a good 16MB in SIMMs for ~$1000 these days,
plus the price of a memory board. Much cheaper than the cache cards I've seen.
Don't forget that you could always use this memory as a buffer cache.

Also, you'll need to make sure that your unix will talk to your controller
card.

---
Alexis Rosen
{cmcl2,apple}!panix!alexis
alexis@panix.uucp