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From: "John S. Dyson" <toor@dyson.iquest.net>
Message-Id: <199701200206.VAA00126@dyson.iquest.net>
Subject: Re: possible madvise MADV_FREE improvement
To: dtc@scrooge.ee.swin.oz.au (Douglas Thomas Crosher)
Date: Sun, 19 Jan 1997 21:06:06 -0500 (EST)
Cc: current@FreeBSD.ORG
In-Reply-To: <199701191019.VAA09832@scrooge.ee.swin.oz.au> from "Douglas Thomas Crosher" at Jan 19, 97 09:19:06 pm
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> 
> Below is a patch which seems to improve madvise MADV_FREE; stops the
> page-ins in the example recently posted.  It also brings the call
> closer to reliably zeroing the pages.
> 
Thanks for the bug report, and I will be committing a fix in a little
while (next hour or so) for the problem.  Note that MADV_FREE does not
guarantee that the page will be zeroed in any way.  Specificially, MADV_FREE
allows the system to optionally dispose of the contents of the page range,
without paging it out.  If the contents are disposed of, of course, the
pages in the page range will be demand zeroed.

John
dyson@freebsd.org