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	Thu, 28 Aug 1997 14:39:26 -0500 (EST)
From: "John S. Dyson" <toor@dyson.iquest.net>
Message-Id: <199708281939.OAA02677@dyson.iquest.net>
Subject: Re: A how does it work question.
In-Reply-To: <199708281639.JAA01045@phaeton.artisoft.com> from Terry Lambert at "Aug 28, 97 09:39:29 am"
To: terry@lambert.org (Terry Lambert)
Date: Thu, 28 Aug 1997 14:39:26 -0500 (EST)
Cc: toor@dyson.iquest.net, terry@lambert.org, Shimon@i-connect.net,
        peter@spinner.dialix.com.au, petrilli@amber.org, smp@FreeBSD.ORG,
        peters@gil.com.au, mestery@winternet.com
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Terry Lambert said:
> > > For a general soloution instead, which will work with all FS's, even
> > > under stacking, a graphical soloution is required.  You precompute
> > > Warshal's over the graph for everything but the next event to be
> > > added.  This lets you (1) recompute it in linear time (O(n)), and
> > > (2) run dependencies between stacked layers.
> > > 
> > Sounds like 72lbs of code to me :-).
> 
> It's not.  It's within 5% of writes to RAM, according to the
> Ganger/Patt paper, which is a less general soloution to the
> problem Soft Updates solves (it's FFS specific).
> 
I hope you didn't take my comment seriously.  I have read all of the
available literature :-).  Another case of my wierd humor backfiring.

John