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Date: Fri, 2 Aug 2002 20:32:10 -0700 (PDT)
From: Linus Torvalds <torvalds@transmeta.com>
To: <davidm@hpl.hp.com>
cc: Gerrit Huizenga <gh@us.ibm.com>, Hubertus Franke <frankeh@watson.ibm.com>,
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Subject: Re: large page patch (fwd) (fwd) 
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On Fri, 2 Aug 2002, David Mosberger wrote:
> 
> The Rice people avoided some of the fragmentation problems by
> pro-actively allocating a max-order physical page, even when only a
> (small) virtual page was being mapped.

This probably works ok if
 - the superpages are only slightly smaller than the smaller page
 - superpages are a nice optimization.

>				  And since superpages quickly become
> counter-productive in tight-memory situations anyhow, this seems like
> a very reasonable approach.

Ehh.. The only people who are _really_ asking for the superpages want 
almost nothing _but_ superpages. They are willing to use 80% of all memory 
for just superpages.

Yes, it's Oracle etc, and the whole point for these users is to avoid 
having any OS memory allocation for these areas.

		Linus

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