Path: utzoo!attcan!uunet!decwrl!bacchus.pa.dec.com!shlump.nac.dec.com!fmcsse.enet.dec.com!heintze
From: heintze@fmcsse.enet.dec.com (Siegfried Heintze)
Newsgroups: comp.sys.ibm.pc.hardware
Subject: 80 mb RLL 28ms Micropolis Drive much slower than Seagate ST251 MFM 28 ms 40MB
Keywords: performance, I/O
Message-ID: <15946@shlump.nac.dec.com>
Date: 10 Oct 90 16:30:15 GMT
Sender: newsdaemon@shlump.nac.dec.com
Reply-To: heintze@fmcsse.enet.dec.com (Siegfried Heintze)
Organization: Digital Equipment Corporation
Lines: 49

I ran out of room with my 28 ms Seagate ST251 MFM 40 mb drive so I purchased a
used
RLL 80 mb RLL 28 ms Micropolis from  Terry - a fellow who has a repair shop in
is home.

I'm running a 10Mhz AT.    I have a make file that that currently requires about
20 minutes
to execute when all the OBJ files are deleted.   I am certain my seagate did not
take this 
long.  In fact, I believe my seagate used to require about 5 minutes to execute
this make
file when starting from scratch.  I'll verify this in a couple of days:  as soon
as I have time
to swap the drives.

I called up Terry.  He was a little defensive and demanded I have some hard
numbers
before I complain.  Well having worked on peformance problems for customer
support,
I can identify with this attitude.   He did say he forgot to run SETUP and
change the drive 
type.  He recommended I run SETUP and change the drive type to 1.  It was set to
40 and I 
changed this to 1.    This seemed to help a little.  I timed the execution of
the make file after switching the drive type (in SETUP) to 1.

Where can I find some documentation on this SETUP program - I am suspicious
because
I have no idea what these numbers mean.

I occiasonally use WINDOWS V3.0 so I have their smartcache in my autoexec.bat. 
Could this
be causing a problem?  (The make file was never run from windows).

How could this be that there is such a drastic desparity in performance between
two 28 ms
drives?  Terry told me,  if anything, the Micropolis should be faster since
seagate often
fudges their performance claims.

This might be a controller problem.  I'm not sure I understand the concept of
interleaving
as it applies to controllers.  An explanation would be welcome.  Terry said this
was not likely to be a  problem with interleaving although I believe I do not
have an interleaved controller.  How can I find out?

                                  Thanks,

                                             Sieg