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From: caf@omen.UUCP (Chuck Forsberg WA7KGX)
Newsgroups: comp.unix.xenix
Subject: Re: Microport -vs- SCO -- which should/would you buy
Message-ID: <620@omen.UUCP>
Date: Sat, 5-Dec-87 20:13:29 EST
Article-I.D.: omen.620
Posted: Sat Dec  5 20:13:29 1987
Date-Received: Thu, 10-Dec-87 23:53:05 EST
References: <388@ddsw1.UUCP>
Reply-To: caf@omen.UUCP (Chuck Forsberg WA7KGX)
Organization: Omen Technology Inc, Portland Oregon
Lines: 42
Keywords: Followup to earlier posting

Here are some of my impressions of the two, from the perspective of a
developer of comm software (Professional-YAM/ZCOMM/DSZ).  Hardware: 386
Intel motherboard, 2.5 MB 32 bit RAM, sometimes 2 MB 16 bit RAM
(slooow), 72 and 30 MB drives, AST dumb 4-port (5 total serial ports).
Microport 286 is run on an AT clone with 20 MB partition on a Seagate
4051.

386 Xenix: 2.2 Xenix 386 runs quickly and smoothly (as long as you don't
let it get near that 16 bit ram).  Compiler passes are native 386 and
run much faster than the older 286 passes.  It's possible to have a make
in the background and forget about it, but news-unpack does slow the
system.  With dumb serial ports, I/O at 19200 bps works well provided
TTYHOG doesn't bite.  At 38k it is possible to bring down the system
with a specific sequence of operations which is very easy to avoid.
Despite numerous power blips etc.  I don't recall losing any files while
running production kernels.

SCO warns not to use 16 bit memory on 386 motherboards.  I have not
seen any problems resulting from this, other than speed.  Code running
from 16 bit memory behaves like a 4 mHz 286 box.  So I only use the
extra memory when running VP/ix.

VP/ix on SCO Xenix: this emulates a virtual machine.  A hacker's
delight, you can switch virtual BIOS roms by pointing to a different
file.  By making a copy of your EGA's rom, you can access 640x480 etc.
modes in graphics programs.  It will be interesting to see how this
product matures.

386 Microport: I only have an early version whose serial I/O was an
unmitigated disaster above 1200 bps.  Unix Pro-YAM did compile on it
without problem.  I've heard that Microport 386 Unix has improved since
then.

286 Microport: Lacks medium and huge memory models.  Unix Pro-YAM is too
big for a fully featured version to fit in the small model, and the
compiler flips out when large model is attempted.  Compiles are rather
slow.

As far as I know, none of the 386 Unix systems have any understanding of
the fact that some memory is fast 32 bit and some is slow 16 bit.  Many
386 boxes have a limited amount of fast 32 bit memory which should be
used for active text and stack segments, not the buffer cache.