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From: David Mosberger <davidm@napali.hpl.hp.com>
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Date: Fri, 2 Aug 2002 21:39:36 -0700
To: Linus Torvalds <torvalds@transmeta.com>
Cc: davidm@hpl.hp.com, Gerrit Huizenga <gh@us.ibm.com>,
       Hubertus Franke <frankeh@watson.ibm.com>, <Martin.Bligh@us.ibm.com>,
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Subject: Re: large page patch (fwd) (fwd) 
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>>>>> On Fri, 2 Aug 2002 21:26:52 -0700 (PDT), Linus Torvalds <torvalds@transmeta.com> said:

  >> I wasn't disagreeing with your case for separate large page
  >> syscalls.  Those syscalls certainly simplify implementation and,
  >> as you point out, it well may be the case that a transparent
  >> superpage scheme never will be able to replace the former.

  Linus> Somebody already had patches for the transparent superpage
  Linus> thing for alpha, which supports it. I remember seeing numbers
  Linus> implying that helped noticeably.

Yes, I saw those.  I still like the Rice work a _lot_ better.  It's
just a thing of beauty, from a design point of view (disclaimer: I
haven't seen the implementation, so there may be ugly things
lurking...).

  Linus> But yes, that definitely doesn't work for humongous pages (or
  Linus> whatever we should call the multi-megabyte-special-case-thing
  Linus> ;).

Yes, you're probably right.  2MB was reported to be fine in the Rice
experiments, but I doubt 256MB (and much less 4GB, as supported by
some CPUs) would fly.

	--david
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