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To: David Greenman <dg@root.com>
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From: Poul-Henning Kamp <phk@dk.tfs.com>
Subject: Re: kern/4070: cannot access over 64MB memory 
In-reply-to: Your message of "Wed, 09 Jul 1997 15:00:01 PDT."
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Date: Thu, 10 Jul 1997 08:17:01 +0200
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>    Malloc is kind of strange when it comes to allocating the virtual address
> space and will consume up to twice the amount requested.

Well, true, but that is not the case here:

The maximum overallocation for any one call to malloc(bytes) is:

	min(pagesize-1, bytes*2-1)

This is because when "bytes" is > pagesize/2, an integral number of
pages is allocated, otherwise a 2^n size chunk is allocated.

--
Poul-Henning Kamp           | phk@FreeBSD.ORG       FreeBSD Core-team.
http://www.freebsd.org/~phk | phk@login.dknet.dk    Private mailbox.
whois: [PHK]                | phk@tfs.com           TRW Financial Systems, Inc.
Power and ignorance is a disgusting cocktail.