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From: caf@omen.UUCP
Newsgroups: comp.sys.ibm.pc
Subject: Re: New Dos from Microsoft
Message-ID: <521@omen.UUCP>
Date: Thu, 16-Apr-87 04:24:22 EST
Article-I.D.: omen.521
Posted: Thu Apr 16 04:24:22 1987
Date-Received: Sat, 18-Apr-87 03:48:53 EST
References: <705@imsvax.UUCP> <631@edge.UUCP> <1622@bnrmtv.UUCP>
Reply-To: caf@.UUCP (PUT YOUR NAME HERE)
Organization: Omen Technology Inc, Portland Oregon
Lines: 15

In article <1622@bnrmtv.UUCP> connery@bnrmtv.UUCP (Glenn Connery) writes:
:> Another consideration:  if'n you put the '286 into protected mode, the
:> CPU *itself* slows way down!  So you end up with a slow CPU running
:> applications which have to do long, slow operating-system calls in order
:> to accomplish a simple "store byte into video buffer".
:> 
:
:1) The 286 runs at least 50% FASTER in protected mode than in REAL mode.
:   If you think about it, this is obvious--REAL mode is a simulation.

On the "siev" benchmark, using the same computer and the same compiler,
siev runs no faster under Xenix (protected mode) than it does under DOS
(real mode).  If anything, real mode is a hair faster.  This applies to
small model programs, large model programs take more cycles to change
segments when in protected mode.