*BSD News Article 19256


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Newsgroups: comp.os.386bsd.development
Path: sserve!newshost.anu.edu.au!munnari.oz.au!news.Hawaii.Edu!ames!elroy.jpl.nasa.gov!decwrl!rtech!amdahl!hip-hop!dfox
From: dfox@hip-hop.suvl.ca.us (David Fox)
Subject: Re: V86 mode
References: <107725@hydra.gatech.EDU> <23tqbk$3tt@europa.eng.gtefsd.com>
Organization: Hip-Hop BBS, Sunnyvale, CA (408-737-8300)
Date: Sat, 7 Aug 1993 05:09:38 GMT
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Message-ID: <CBDIC3.Gp4@hip-hop.suvl.ca.us>
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David C. Niemi (niemidc@oasis.gtefsd.com) wrote:
: The V86-mode emulators I have seen tend to suck about 10% of the CPU each (on a 386).
: Is this inherent in V86 mode, or is it a deficiency of the implementation?
I am sure some of the performance hit you get with dosemu and v86 mode in
general is because the system is already in protected mode, and there is
significant anction to switch between the two modes, and linux is continually
switching between the two when running dosemu.  I don't think the problem is
unavoidable, because in part that is how the intel hardware does things.

BTW, I tried dosemu on a 386SX running linux, and the DOS programs running
underneath were really too slow to use.
: In other words, have you gotten around this problem?
: ---
: David C. Niemi: David.Niemi@oasis.gtegsc.com


-- 
David E. Fox                                   email: hip-hop!dfox@amdahl.com
5479 Castle Manor Drive                   
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