Newsgroups: comp.os.mach
Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!ispd-newsserver!ism.isc.com!ico!rcd
From: rcd@ico.isc.com (Dick Dunn)
Subject: Re: Does Mach386 use BIOS?
Message-ID: <1991Mar28.200333.13563@ico.isc.com>
Summary: BIOS probably not a good idea
Organization: Interactive Systems Corporation, Boulder, CO
References: <2053@pdxgate.UUCP>
Date: Thu, 28 Mar 1991 20:03:33 GMT

berggren@eecs.cs.pdx.edu (Eric Berggren) writes:

>   I am in the midst of a small war debating whether or not one should
> use system BIOS where it is available. One side is arguing compatibility
> and the other side is pushing performance. At one time, I was for BIOS on
> everything, but after experience and readings of various articles, I
> currently stand on the side of direct hardware interfacing...

Mach doesn't use the BIOS, as already noted here.  Nor do System V or BSD
for the 386.  The reasons are that the normal BIOSes run in real mode,
where any reasonable 386 OS wants to run in protected mode.  They're also
16-bit where you want 32, and they're essentially single-threaded.  The
performance hit for getting in and out of the BIOS and getting data to/from
where you want it makes it impractical for devices where performance matters
(like disk).
-- 
Dick Dunn     rcd@ico.isc.com -or- ico!rcd       Boulder, CO   (303)449-2870
   The Official Colorado State Vegetable is now the "state legislator".