From owner-freebsd-current  Wed Sep  2 00:51:38 1998
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	Wed, 2 Sep 1998 17:50:31 +1000
Date: Wed, 2 Sep 1998 17:50:31 +1000
From: Bruce Evans <bde@zeta.org.au>
Message-Id: <199809020750.RAA15197@godzilla.zeta.org.au>
To: jdp@polstra.com, tlambert@primenet.com
Subject: Re: ELF binaries size
Cc: bde@zeta.org.au, current@FreeBSD.ORG, reilly@zeta.org.au
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>> > I think it implies that elf wastes a full page of memory (the space
>> > between the ':'s above) most of the time (unless the ':'s are on a
>> > page boundary), while aout only wastes an average of half a page
>> > (the space between the text ':' and the end of the page).
>> 
>> But a.out has a repeat of the same situation at the juncture of data
>> and bss, and ELF does not.
>
>In the disk image rather than in the memory image.
>
>I think Bruce is mistaking the dual mapping for a single mapping,
>on the theory that in a unified VM and buffer cache, there can be
>only one instance of a page hung off the VP.

Nah.  The dual mapping is precisely what costs a full page of real memory.

Bruce

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