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From: "John S. Dyson" <toor@dyson.iquest.net>
Message-Id: <199608271710.MAA00624@dyson.iquest.net>
Subject: Re: The VIVA file system (fwd)
To: terry@lambert.org (Terry Lambert)
Date: Tue, 27 Aug 1996 12:10:14 -0500 (EST)
Cc: dyson@FreeBSD.org, terry@lambert.org, sysseh@devetir.qld.gov.au,
        freebsd-fs@FreeBSD.org, eric@ms.uky.edu
In-Reply-To: <199608271533.IAA24689@phaeton.artisoft.com> from "Terry Lambert" at Aug 27, 96 08:33:53 am
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> > I am tonight porting LFS, maybe with some luck will get it to work.  However,
> > the FreeBSD VM/Buffer cache stuff affects the filesystem only slightly esp.
> > now.  The biggest issue in porting from the old Lite stuff is getting
> > rid of gratuitious vnode_pager_uncaches, and changing the ordering of
> > some operations slightly.
> 
> Any chance you can replace them with a null macro, instead of just diking
> them out, in order to make the code less VM implementation dependent?
> 
I'll try, but my main purpose is:

	1)	A diversion, because even though I love the VM stuff, I am
		kind-of tired of it right now.
	2)	Get enough of it running, so that someone else can make it
		work "well" and/or productize it.  My mainline plate is
		overwhelmingly full.
	3)	The fact that LFS hasn't been working is a festering sore,
		and I am mostly putting anti-bacterial ointment on it :-),
		so the limb doesn't fall off :-).

Most, if not all of the changes that I am making are bugfixes.  The frequency
of vnode_pager_uncache use in the old fs code (for example) is simply wrong,
and if I work on LFS too much, it'll simply get rewritten to aggressively use
the VM system and elimimate lots of very evil copies :-).  Then, diffs or
ifdefs will be of NO value :-).

John