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From: Marvin Justice <mjustice@austin.rr.com>
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To: "H. Peter Anvin" <hpa@zytor.com>, linux-kernel@vger.kernel.org
Subject: Re: highmem question
Date: Fri, 7 Dec 2001 19:30:01 -0600
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>
> > I heard that himem slows down systems.
>
> It does, because it's a hack to extend 32-bit machines beyond their
> architectural lifetime.
>

While it certainly makes sense to expect a performance hit for mem above 4GB 
on 32 bit systems I don't see why there should be any a priori reason to 
either move to 64 bit or take a performance hit for if you need, say,  2GB of 
RAM. The problem is that 2.4 Linux considers HIGHMEM to be anything above 
896MB. 

>From what I've read it looks like there will be changes in 2.5 to fix all 
this.

Marvin Justice
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