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Date: Wed, 03 Mar 2004 00:30:15 -0500
From: Chuck Swiger <cswiger@mac.com>
Organization: The Courts of Chaos
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To: Jamie <jamie@gnulife.org>
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cc: freebsd-questions@freebsd.org
Subject: Re: Swap space - max size
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Jamie wrote:
>    Is there any point in adding more than 2 Gb of swap space on an x86 if
> you have 2 Gb of ram?

Yes.

> From what I've read, x86 can address 4 Gb of memory,
> so it would seem that more than 4 Gigs of combined memory and swap space
> would be wasted. Am I right?

You would be right if all of the memory was only being used by one process. 
However, each process has it's own 4GB of virtual address space, although 
typically the top 1 GB is actually shared (ie, is used by the kernel), and 
other complications (like using SysV shared memory) can change this further.

-- 
-Chuck