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To: Andrey Chernov <ache@nagual.pp.ru>
From: "Poul-Henning Kamp" <phk@phk.freebsd.dk>
In-Reply-To: Your message of "Fri, 04 Jan 2008 16:12:47 +0300."
	<20080104131247.GA17816@nagual.pp.ru> 
Date: Fri, 04 Jan 2008 13:28:39 +0000
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Cc: freebsd-current@FreeBSD.ORG, Jason Evans <jasone@FreeBSD.ORG>
Subject: Re: sbrk(2) broken 
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In message <20080104131247.GA17816@nagual.pp.ru>, Andrey Chernov writes:
>On Fri, Jan 04, 2008 at 12:57:11PM +0000, Poul-Henning Kamp wrote:
>> There is address space allocated to the process (via sbrk/mmap)
>> 
>> A subset of this, is address space allocated by the program (via malloc)
>> 
>> ...and then there is memory actually in use, which is an entirely different
>> thing, of which we currently only have some kind of clue in the VM
>> system.
>
>Then, we need sysctl to fetch that "memory actually in use" from the 
>kernel and compare that with getrlimit() which allows malloc() to return 
>0 when needed.

No we don't.

Find a book that explains how Virtual Memory works.

-- 
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.