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Date: Mon, 21 Feb 2005 07:42:17 -0700
From: Scott <scottl@samsco.org>
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To: Petri Helenius <pete@he.iki.fi>
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cc: freebsd-hackers@freebsd.org
Subject: Re: 4M page size
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Petri Helenius wrote:
> 
> Is there a way currently to utilize 4M page size with FreeBSD for large 
> data set programs (to optimize TLB misses)?
> 
> Pete
> 

FreeBSD/i386 uses 4MB pages to hold the kernel text and data, but there
is no way (to my knowledge) to ask the pmap layer for a 4MB page after
that either from the kernel or from userland.  However, it's also my
understanding that most non-Xeon CPUs only have a 4kb TLB, and 4MB pages
are just broken down into 4kb chunks for it.

Scott