386 capacity running xenix - summary of responses
Farhad Khansefid
farhad at corwin.usc.edu
Mon Mar 7 12:57:31 AEST 1988
Thanks to those who responded to my query. I basically wanted to know
how far can one push a 386 machine running xenix and what are the
limiting factors (disk space, ram, multi serial ports ...etc.) to
consider. Following is an edited summary of the responses I got.
( By the way, I am still very much interested in hearing your comments
and experiences in using a 386 machine running sco xenix. Please mail
to farhad at corwin.usc.edu and i will summarize again if necessary.)
======================
FROM: Dean Brunette at oliveb!olivej!dragon at ames.arc.nasa.gov
SYSTEM: 20mhz 386 machine running SCO XENIX, 8Meg RAM , 2 AST 4-port cards.
I have Up to five users running on it with no great performance
degradation, until they started doing CPU or disk intensive tasks. I
think two important things that improve performance are: high
performance drives (you'll notice a *big* increase in speed with an
18ms drive over a 28ms, and if you have two different drives that will
help too), and lots of RAM (I have 8 megs, and it's not enough for 8
users... the thing was terribly slow with only 4 megs). I have 8
serial ports on the beast without using smart ports yet (two AST
4-port cards).
=====================
FROM: James R. Van Artsdalen !uunet!utastro!bigtex!james at astro.as.utexas.edu
SYSTEM: ?
The limiting factor in unix (or xenix) performance is not really any of
the factors you mentioned, but the amount of RAM in the system. Put in
2meg + 512K / light-user or + 1meg for a heavy user.
=====================
FROM: Paul Lucchina at hsi!lucchina at uunet.UU.NET
SYSTEM: [will purchase] Compaq 386/20 with a 300 Mb disk / 5 Mb of memory.
We will be running Santa Cruz Xenix 386 OS. Santa Cruz refered me to
a consuting firm in Hartford, CT. They have integrated 32 user
systems utilizing this config. The consultants at this firm are real
purists and have given me a lot of tips on getting the maximum
performance out of this box. Here are some of them: If you don't need
the monochrome display and adapter for console don't bother purchasing
on. It is a hog on interrups and you can install SCO from the com
=====================
FROM: Robert Boucher at sco!robertb at uunet.UU.NET
SYSTEM: 286
Even though the company [sco -ed.] probably has some "official
figures," the group that I'm in is currently running 11 users on a
286. The machine gets sluggish sometimes (when people start running
informix :-(), but it serves us well...
(Just to add to the figures, our group is doing simple things like
reading mail, news, occasional compiles, etc.)
=======================
From: Andrew Beattie <ames!lll-lcc!uunet!mcvax!sphinx.co.uk!andrew%ll-xn.UUCP at oberon.usc.edu>
SYSTEM: some compaq 386/16 with 130Meg, will gte 386/20 with 300Meg. Chase AT8
>
> - How does the performance degrade compared
> to a one or two user system?
>
Not much different - still impressivly fast
>
> - Did you have to use Smart serial ports?
>
Yes - Chase AT8, but now we go in by TCP/IP using an Excelan Board
>
> - How far do you think one can push a 386?
>
I would Guess at about 16 or more, if you have lots of memory but try as
we might we never seem to overload the machine (I am in a
department of 10 Techies running a 4GL database and all the products
we have to support) )
>
> - Would 28ms disk access time be sufficient
> or you need to spend some buck for 18/16.5 ms?
>
Dunno - we run several Compaq 386/16 with 130Meg disks (we are getting
a 386/20 with 300Meg real soon now)
====================
More information about the Comp.unix.xenix
mailing list