Re: [RFC] 4-level page table directories.

Robin Holt
2005-11-02T16:23:58Z

On Wed, Nov 02, 2005 at 08:11:10AM -0800, Luck, Tony wrote:
> >We then started discussing this. For a normal application with the
> >same virtual address requirements run on a 4 versus a 3 level page table,
> >we would end up with, at most five additional pages of page tables with
> >a single cache-line used in each.
>
> What about AIM7? The extra pages would make a difference on a small
> memory machine running thousands of processes. Is that a concern for
> anyone?

On the aim7 runs I did on a 4 cpu, 4GB machine it was in the noise
range with the 4-level kernel outperforming on nearly an equal number
of points to the 3-level.

Robin