Subject: Re: ASUS
To: Hacksaw <hacksaw@venus.gsd.harvard.edu>
From: James da Silva <jds@cs.umd.edu>
List: netbsd-help
Date: 11/17/1995 21:16:48
 > Does anyone know whether the ASUS dual processor motherboard is a
 > problem with NetBSD? I realize the kernel isn't setup for
 > multiprocessing, but I am assuming there's a way for the thing to just
 > ignore the extra one. I am thinking of playing with Mach, as well as
 > regular NetBSD, so...

The dual processor boxes work just fine as straight PCs, even with two
processors in them.  The Intel MP specs require that.  After the BIOS
initialization, the second Pentium stays halted until it gets an interrupt
from the boot processor.  I'm running NetBSD on a ASUS dual P90 box right
now, no problem.

Be warned that because of the shared L2 cache, you are going to get little
performance benefit from the second processor, except for applications with
working sets that fit in the small on-chip L1 cache.  And remember that
even if you get throughput that is 140% of a single processor, that means
that each cpu is running at only 70% of its potential, increasing latency
for individual tasks.  (This is assuming an OS that uses the second
processor, of course.  NetBSD doesn't.)

In my opinion, the only reason to get a dual Pentium is to play with SMP
issues on the cheap, like I did.  Otherwise you're better off spending the
extra money on more memory and/or a jazzier graphics card, better disk
controller, monitor, or whatever.

IMHO,
Jaime
..............................................................................
:  James da Silva  :  UMCP Computer Science Dept  :  Stand on my shoulders,  :
:  jds@cs.umd.edu  :  http://www.cs.umd.edu/~jds  :  not on my toes.         :