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From: "John S. Dyson" <toor@dyson.iquest.net>
Message-Id: <199605150029.TAA13410@dyson.iquest.net>
Subject: Re: A question for the VM gurus..!
To: jgreco@brasil.moneng.mei.com (Joe Greco)
Date: Tue, 14 May 1996 19:29:58 -0500 (EST)
Cc: hackers@freebsd.org, dyson@freebsd.org
In-Reply-To: <199605142254.RAA11225@brasil.moneng.mei.com> from "Joe Greco" at May 14, 96 05:54:01 pm
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> 
> Summary:  curious about the status of madvise/mincore.
> 
> A quick find /usr/src/sys -type f -print | xargs grep MADV reveals that 
> the MADV constants aren't used anywhere in the kernel (at least on my
> 2.1R systems).
> 
> I see madvise and mincore return EOPNOTSUPP.
> 
> Do we have any plans to support this, for those of us who would prefer to
> keep our VM systems more informed?
> 
Mincore is supported in current (but only approximately correctly -- it returns
which pages are mapped in a process, not actual residency.)  It says in essence,
which pages don't have to be faulted...  I have been planning on fixing that.
Perhaps we should implement a more fully featured mincore -- I did some
mods for Ron Minnich, and since we have a full byte, we would have 8 bits
of info about the pages that we could present :-).  I am sure that the
API gods would have something to say about that though.  (I never liked
rules, but they are necessary.)

Madvise is on my list (and probably only a few hours of work to do correctly.)
If you bug me right before the weekend -- I was planning on going to the Dayton
Hamfest, but I don't think I have time now -- I might be able to put something
into -current over the weekend...  This is a squeaky wheel situation :-).

John