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From: jsa@alexandria.organon.com (Jon S Anthony)
Subject: Re: Tasking Techniques - Opinions?
Date: 1997/06/10
Message-ID: <JSA.97Jun10131945@alexandria.organon.com>#1/1
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Date: 1997-06-10T00:00:00+00:00
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In article <dewar.865692193@merv> dewar@merv.cs.nyu.edu (Robert Dewar) writes:

> Jon says
> 
> <<> Absolutely true.  However, do be aware that protected types have
> > significant overhead -- not as much as task rendezvous, but on the
> > order of ten times a procedure call.
>  
> I find this surprising. On what do you base this 10X figure?
> >>
> 
> surprisingly low? or suprisingly high? The difference will vary widely. If

Actually, I was thinking "high".

> taking the necessary lock requires a kernel call, as it does when running
> over some OS's, then the factor of 10 will be wildly optimistic. Protected
> types were designed to be efficient on bare hardware, their implementation
> over operating stystems is often disappointingly inefficient.

OK, that makes good sense.

/Jon
-- 
Jon Anthony
Organon Motives, Inc.
Belmont, MA 02178
617.484.3383
jsa@organon.com