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Date: Mon, 23 Feb 2009 15:16:11 -0500
From: Bill Moran <wmoran@potentialtech.com>
To: Christian Peron <csjp@freebsd.org>
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Cc: Kirk Strauser <kirk@strauser.com>, Garrett Cooper <yanefbsd@gmail.com>,
	"Brian A. Seklecki" <lavalamp@spiritual-machines.org>,
	freebsd-hackers@freebsd.org
Subject: Re: shmmax tops out at 2G?
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In response to Christian Peron <csjp@freebsd.org>:

> On Mon, Feb 23, 2009 at 11:58:09AM -0800, Garrett Cooper wrote:
> [..]
> > 
> > 	Why isn't the field an unsigned int / size_t? I don't see much value 
> > in having the size be signed...
> 
> No idea :) This code long predates me. 

It's that way because the original Sun spec for the API said so.

It makes little sense to change it just to unsigned.  The additional 2G
it would give doesn't really solve the tuning problem on a 64G system.
This is simply a spec that has become outdated by modern hardware.

-- 
Bill Moran
http://www.potentialtech.com
http://people.collaborativefusion.com/~wmoran/