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To: Alan Cox <alc@rice.edu>
Subject: Re: Behavior of madvise(MADV_FREE)
In-reply-to: <5082F0F3.1070102@rice.edu>
From: "Poul-Henning Kamp" <phk@phk.freebsd.dk>
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Date: Sat, 20 Oct 2012 19:34:56 +0000
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Cc: Tim LaBerge <tlaberge@juniper.net>,
 "freebsd-arch@freebsd.org Arch" <freebsd-arch@FreeBSD.org>,
 Jason Evans <jasone@FreeBSD.org>, Marcel Moolenaar <marcel@xcllnt.net>
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--------
In message <5082F0F3.1070102@rice.edu>, Alan Cox writes:

>I'm sympathetic.  Once upon a time, I was often called upon to explain 
>to network administrators why their idle web cache didn't have oodles of 
>"free" memory and how this wasn't a problem.

You too ?   :-)

>I think that you're being a bit too pessimistic here.  If your use case 
>really corresponds to "this memory is free and will not be reused (or 
>reallocated for a very long time)"

Which brings me to a question I have wondered:  Why not simply
munmap(2) it until you need it again ?

-- 
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.