Re: large page patch (fwd) (fwd)

David S. Miller
2002-08-06T05:08:33Z

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.