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From: Peter Schuller <peter.schuller@infidyne.com>
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Date: Wed, 9 Jan 2008 19:22:47 +0100
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Cc: Andrew Reilly <andrew-freebsd@areilly.bpc-users.org>,
	Peter Jeremy <peterjeremy@optushome.com.au>,
	Poul-Henning Kamp <phk@phk.freebsd.dk>,
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	Kostik Belousov <kostikbel@gmail.com>,
	Dag-Erling =?iso-8859-1?q?Sm=F8rgrav?= <des@des.no>
Subject: Re: sbrk(2) broken
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> Actually, malloc(3) can use madvise(2) to notify the kernel that
> arbitrary pages in the arena are unused and can be discarded.  The
> current implementation will do so if the H option is specified.

Ah, interesting. I was not aware of that.

However, in this context it will likely only help partially since you still=
=20
need a full page to be free (and with a lot of programs many allocations wi=
ll=20
be significantly smaller than that, and I have to assume no real-life mallo=
c=20
will align all allocations to pages, or the overhead would be extreme).

=2D-=20
/ Peter Schuller

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