Path: utzoo!utgpu!news-server.csri.toronto.edu!rutgers!usc!samsung!umich!sharkey!nstar!towers!robert
From: robert@towers.UUCP (Robert Hoquim)
Newsgroups: comp.unix.sysv386
Subject: Re: Recommendations for fixed-disk SCSI Controllers
Message-ID: <285@towers.UUCP>
Date: 5 Jan 91 20:28:42 GMT
References: <1990Dec28.233946.7381@csn.org> <37532@cup.portal.com>
Distribution: na
Organization: The Twin Towers - Indianapolis, IN  USA
Lines: 43

DeadHead@cup.portal.com (Bruce M Ong) writes:

>The Interactive Release Notes for 2.2 says on page 19 that on machines
>with SCSI primary adapters and multiple SCSI fixed disks doing very heavy
>disk I/O, the kernel may panic or the system may hang. Has anybody
>experienced this problem with Future Domain or Adaptec host adapters?

This is a problem on some very fast systems with fast drives that have
synchronous ability on 2 or more drives.  Under heavy load I have several
systems that will fail on a regular basis.  With the 2.2.1 fix the problem
has gone away completely so it is no longer an issue.  If you have this
problem it may be hard to get ISC to send you the fix but it will correct
your problem.

Also on the subject of SCSI.  I have in beta test our custom drivers for
the Mylex DCE EISA Caching controller.  They will support ISC 2.02 and
above on all Mylex MAE, ALR, HP and many other EISA mother boards that use
the newest EISA chip set from Intel.  There seem to be several revisions of
these chips and some companies are running the 25mhz set at 33mhz.  Due to
the performance we are demanding of these controllers everything must be
done right and many EISA MB builders just don't have it right yet.  Be very
careful of any EISA you choose, I have seen some real junk in the clone
world.  One wonders if they even tested the MB with an EISA card... :-).

The performance of this controller is overall, 4 times faster than a 1542
on a similar machines of the supported BUS. (ISA/EISA) (Please remember
that a 1542 on a EISA mb will run but it will run slower than it will on a
system of the same speed with an ISA MB due to the "BusMaster" design.)  So
all 1542 test were run on a 486-33 ISA where the DCE tests were run on a
486-33 EISA.  We also have drivers for SCO and Esix in the works due to be
released in the next few months.

For those that are interested please drop a note and we will send you a
list of several benchmarks that have been run on this combination. Tape
support will also be available in the final release.  

                                                  Bob Hoquim

-- 
Robert Hoquim                                   Small Systems Specialists
(317)-255-6807 (Voice)                          8500 N. Meridian
robert@towers or towers!robert                  Indianapolis, IN.  46260
 -- Providing HIGH Performance Unix Systems to YOU is Our ONLY goal!  --