Re: [PATCH 4/4] vmm: Use a static memory map

Christoph Lameter
2006-10-13T00:29:35Z

On Thu, 12 Oct 2006, Luck, Tony wrote:

> > So, the size of the virtual memory map is always less than 8 Terabyte.
>
> 32 TB for 4K pagesize using current physical address space limit and
> existing Linux sizeof(struct page)

Ok. Well in that unlikely case we can probably sacrifice more?

> > I think its reasonable to take these 8 Terabyte away from the 128 Terabyte
> > that we currently reserve for support for VMALLOC space.
>
> Does it still sound as good to take 32/128 TB? What if the physical
> address space gets another 4 bits ... even with a 16K pagesize you'd
> need the whole 128TB.

The limits discussed here are for 3 level page tables. All of this gets
much bigger with 4 level page tables.