9fans archive / 1995 / 08 / 47 /    prev next

From: Daniel Egnor egnor@pri...
Subject: 387 required? *and* Memory errors? Mothra sucks?
Date: Sat, 5 Aug 1995 01:36:19 -0400

In article <199508050446.AA26993@int...>,
Steven Plite  <9fans@cse...> wrote:
>Is a 387 required to run the 4-floppy dist on a 386?  The hardware 
>requirements in the install docs don't say so, but the section on the 386 
>compiler in "The Various Ports" says "...the compiler assumes i387-compatible 
>hardware...".

I have successfully installed and booted Plan 9 on a 386 sans 387.  It seems
to work, except that floating-point operations fail with bogus results -- the
only immediate result of this is that the 8 1/2 clock gizmo does not draw the
hands correctly (or at all), since doing so requires trig.  :)

I assume other things break, too.

This same installation crashes after being alive for more than a minute or
two.  I believe this is due to a faulty memory configuration (gah) but have
not verified -- it *could* be due to lack of a coprocessor, but I rather 
doubt it.

Additional topics:

It appears (on a more stable system!) that Plan 9 deals very poorly with memory
errors.  For example, a simple recursive rc function, which a beginner can
easily make accidentally, for example:

  fn ls { lc -F }

(If you're clever you'll figure out why this loops -- it took me a while, since
I wasn't used to the system) will very quickly cause an 8MB machine to scroll
"No physical memory" messages all over the screen.  Unless one is very quick
to kill the offending shell (which is difficult with messages coursing all
over one's screen!) the system crashes.  This is poor.  Have I misconfigured
somehow?  Perhaps I should add some swap space or something?

Along similar lines, when Plan 9 boots, it prints a message about the amount
of memory available, and invariably (even when booting from floppy!) prints
some _large_ amount of swap available (like 50MB).  Why does it do this?

OK, an unrelated gripe: Why is Mothra just an ordinary old Web browser,
except with a lame interface (and a lot of bugs)?  Given Plan 9, I'd think
you'd have something like a urlfs, which would be terribly handy, and an HTML
browser on top of that... am I missing something?

(Don't get me wrong, I love a lot of the concepts in Plan 9, I'm just wondering
about some of the smaller issues.  I do not yet have the CD, BTW.)

Dan