From: "Rafael J. Wysocki" <rjw@sisk.pl>
To: "Sandeep Kumar" <sandeepksinha@gmail.com>
Subject: Re: PAE and PSE ??
Date: Sun, 22 Oct 2006 12:15:26 +0200
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Hi,

On Sunday, 22 October 2006 08:29, Sandeep Kumar wrote:
> Hi all,
> I have read in UTLK by bovet that the linux kernel does not uses the
> PSE bit on an x86
> machine. Then how come we have the hugetlbfs, which provides support
> for 4MB pages ?

AFAIK, PSE is only used when PAE is not set and then it enables the 4 MB
pages.  If PAE is set, the 4 MB pages are impossible because there are only
512 entries per page table, but 2 MB pages can be used instead (and you don't
need to set PSE to use them).

Greetings,
Rafael


-- 
You never change things by fighting the existing reality.
		R. Buckminster Fuller
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