Re: Getting big areas of memory, in 2.3.x?

Kanoj Sarcar
1999-12-09T20:31:15Z

>
> Ingo Molnar wrote:
> > hm, does anyone have any conceptual problem with a new
> > allocate_largemem(pages) interface in page_alloc.c? It's not terribly hard
> > to scan all bitmaps for available RAM and mark the large memory area
> > allocated and remove all pages from the freelists. Such areas can only be
> > freed via free_largemem(pages). Both calls will be slow, so should be only
> > used at driver initialization time and such.
>
> Would this interface swap out user pages if necessary? That sort of
> interface would be great, and kill a number of hacks floating around out
> there.
>

Swapping out user pages is not a sure shot thing unless Linux implements
reverse maps, so that we can track which page is being used by which pte.

Without rmaps, any possible solution will be quite costly, if not an
outright hack, IMO.

Rmaps is probably not happening in 2.3.

Kanoj