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Date: Mon, 05 Aug 2002 21:58:17 -0700 (PDT)
Message-Id: <20020805.215817.05805181.davem@redhat.com>
To: davidm@hpl.hp.com, davidm@napali.hpl.hp.com
Cc: rohit.seth@intel.com, frankeh@watson.ibm.com, torvalds@transmeta.com,
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Subject: Re: large page patch (fwd) (fwd)
From: "David S. Miller" <davem@redhat.com>
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   From: David Mosberger <davidm@napali.hpl.hp.com>
   Date: Mon, 5 Aug 2002 22:01:16 -0700
   
   In my opinion, this is perhaps the strongest argument *for* a separate
   "giant page" syscall interface.  It will be very hard (perhaps
   impossible) to optimize superpages to work efficiently when the ratio
   of superpage/basepage grows huge (as, by definition, the kernel would
   manage them as a set of basepages).

Actually, this is one of the reasons there was a lot of research into
using sub-page clustering for large mappings in the TLB.  Basically
how this worked is that for a superpage, you could stick multiple
sub-mappings into the entry such that you didn't need a fully
physically contiguous superpage.

It's talked about in one of the Talluri papers.
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