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To: David Schultz <das@FreeBSD.ORG>
From: "Poul-Henning Kamp" <phk@phk.freebsd.dk>
In-Reply-To: Your message of "Wed, 07 Jan 2004 20:28:16 PST."
             <20040108042816.GA1813@VARK.homeunix.com> 
Date: Thu, 08 Jan 2004 08:45:13 +0100
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cc: Alexander Leidinger <Alexander@Leidinger.net>
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cc: Peter Jeremy <peterjeremy@optushome.com.au>
Subject: Re: perl malloc slow? 
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In message <20040108042816.GA1813@VARK.homeunix.com>, David Schultz writes:

>FWIW, you can do the required gymnastics with mmap() as long as
>the mapped region is backed by a file.

There has been a lot of talk about using file backing instead of
swap backing.  The typically proposed scenario is for each process
to open "$HOME/.backingstore/$$" or some such.

There are a lot of interesting applications, good ideas and nifty
tricks enabled by this, but there are also some nasty details, a
few security concerns and probably a performance impact.

All in all it has not happened yet, and given the size of fish
we are currently catching in other areas, I don't see it happening
anytime soon.

-- 
Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
phk@FreeBSD.ORG         | TCP/IP since RFC 956
FreeBSD committer       | BSD since 4.3-tahoe    
Never attribute to malice what can adequately be explained by incompetence.