Re: large page patch (fwd) (fwd)

David Mosberger
2002-08-03T04:36:16Z

>>>>> 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