From: sje@xylos.ma30.bull.com (Steven J. Edwards)
Newsgroups: comp.os.coherent,comp.bbs.waffle
Subject: Re: Waffle vs. UUCP/rn on Coherent?
Date: 14 Aug 92 20:57:49 GMT
Reply-To: sje@xylos.ma30.bull.com
Organization: Bull HN, Worldwide Information Systems, Billerica, Mass., USA

In article <BLwHPB4w165w@mantis.co.uk> mathew@mantis.co.uk (mathew) writes:
# You could always consider MINIX.  It doesn't cost much more than Coherent,
# and you can get gcc, a UNIX-like news system and several newsreaders for it.

I am already quite familiar with MINIX and its history.  I expect that
most readers of this group are also aware of MINIX and its newsgroup.

# Advantages of MINIX:
#
# You get the full source code, unlike Coherent, so you can fix anything that
# needs fixing and add extra features if you need them.

Ah, but the main reason that the source code is supplied is because
it's necessary; the user is also expected to also act as the
completion and maintenance staff for an unfinished product.

# It runs on IBM PCs, Macs, Amigas and Atari STs, unlike Linux and Coherent
# which I gather are stuck with the brain-dead Intel architecture.  Software is
# reasonably portable between the platforms if you're careful.

The great benefit of Coherent 4.0 is that it allows one to forget
about Intel segmentation.  I will not bother with an OS religious
debate with respect to platform architecture; my feeling is that if
the OS forces (or even mildly encourages) proficiency with extensive
low level details, then the OS fails in its most important task: to
allow programmers to concentrate on solutions instead of the system
that (allegedly) supports the development of such solutions.

I've read many, many posts in comp.os.minix, and by far and away most
of them were about solving MINIX problems, not about applications and
solutions made posible by MINIX.  The most critical of these, ease of
development of 32 bit applications and wide coverage of hard drive
support, are already solved and supported in Coherent 4.0.

# It runs on an 8088 or even an 8086 if that's all you have.

Ah, but what will it run?  Unprotected small model binaries at best.

# Disadvantages:
#
# If you want to get MINIX-PC and use memory models bigger than 64K+64K, you'll
# have to pick up the 386 patches from the net.

Ah, but where is the support?  The sad truth is that Tannenbaum or
Prentice Hall (or both) are not that interested in keeping the
"official" MINIX base up to date with net output, at least as far as
I've seen.  The 32 bit patches have been around for a long time and I
don't think that they have yet been integrated.

It is true that MWC is not always as fast with new stuff as we would
like (who is?), but they have a track record of showing commitment
towards fixing old stuff and introducing new stuff.

I will agree that Tannenbaum has shown a commitment for those with
outdated platforms like 4.77 MHz 8088 machines.  But is this a
critical need anymore?  If so, why did MWC drop its old 8088 Coherent?
I think that anyone that spent enough money on education (or intends
to spend such in the future), is not going to worry too much about
spending US$1000 for a 386 box.

# The source code isn't freely redistributable, although you can distribute
# your patches as you wish.

I can distribute the code and source for my (personal) Coherent
applications.  I will let MWC worry about the kernel; I wrote an
interrupt driven multiprocessing system fifteen years ago.  It worked
fine and so I feel no big need to write or maintain another one.

# The C compiler provided isn't ANSI (although gcc is available).

People are currently working on porting gcc to Coherent 4.0, I wish
them the greatest of speed.  I am willing to help them test the
compiler with very extensive ANSI test suite of my very own.

# No virtual memory.  (Actually, I don't know whether 386 MINIX has it or not. 
# Go ask comp.os.minix.)  I survived quite happily running news and mail on a
# 1MB Atari ST, so it shouldn't be a problem unless you want to have lots of
# simultaneous users.

Twenty five years ago, fast solid state memory cost about four
thousand times as much ber bit as did rotating mass storage.  Today
the difference factor is about a thousand times less.  Similarly, the
arguments in favor of virtual memory support have also been reduced by
a similar factor.

In summary, I think that both Coherent and MINIX are decent products,
but they are really targeted towards different audiences.  For those
who are unfamiliar with kernel implementation details and other such
items, MINIX (including reading the book) is a good first step,
particularly if the user has access to the net.  On the other hand,
Coherent is a better deal for those whose interest is in research
application development with a multiprocessing environment; a
developer can spend less time diddling with the OS and more time
solving real problems.

 [The above opinions expressed are my own; not necessarily held by others.]
      == Steven J. Edwards           Bull HN Information Systems Inc. ==
      == (508) 294-3484              300 Concord Road         MS 820A ==
      == sje@xylos.ma30.bull.com     Billerica, MA 01821          USA ==
"That Government which Governs the Least, Governs Best." -- Thomas Jefferson
Newsgroups: comp.os.coherent
Subject: Re: Prospective Coherent buyers question