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From: collinge@uvicctr.UUCP
Newsgroups: comp.sys.atari.st
Subject: Re: multitask discussion
Message-ID: <226@uvicctr.UUCP>
Date: Sat, 14-Feb-87 19:18:05 EST
Article-I.D.: uvicctr.226
Posted: Sat Feb 14 19:18:05 1987
Date-Received: Sun, 15-Feb-87 16:03:04 EST
References: <8019@decwrl.DEC.COM>
Reply-To: collinge@uvicctr.UUCP (Doug Collinge)
Organization: University of Victoria, Victoria B.C. Canada
Lines: 23

In article <8019@decwrl.DEC.COM> goldstein@delni.dec.com (Fred R. Goldstein dtn226-7388) writes:
>
>    One proposal (in the discussion of porting MINIX) said that you could 
>    outswap each task (into memory, not physical disk) every time the 
>    context swapped. That sounds a bit slow ...

No, no, no.  You don't have to swap EVERY time you change contexts - only
just after you fork and until you do an exec.  Nearly always you exec
immediately so you do one swap at most.  One swap per exec doesn't seem
exorbitant to me; in fact, I use a system that does things this way and
it is quite successful swapping to disk.  A RAM swap would work even better.
The only case where you have to swap a lot is where you have both a parent
and its child (which doesn't exec) executing at the same time. This
basically doesn't happen - only in very rare cases and we can get around
those, too, with little trouble.
-- 
		Doug Collinge
		School of Music, University of Victoria,
		PO Box 1700, Victoria, B.C.,
		Canada,  V8W 2Y2  
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