Re: [PATCH 44 of 66] skip transhuge pages in ksm for now

Mel Gorman
2010-11-18T16:06:30Z

On Wed, Nov 03, 2010 at 04:28:19PM +0100, Andrea Arcangeli wrote:
> From: Andrea Arcangeli <aarcange@redhat.com>
>
> Skip transhuge pages in ksm for now.
>
> Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
> Reviewed-by: Rik van Riel <riel@redhat.com>

Acked-by: Mel Gorman <mel@csn.ul.ie>

This is an idle concern that I haven't looked into but is there any conflict
between khugepaged scanning the KSM scanning?

Specifically, I *think* the impact of this patch is that KSM will not
accidentally split a huge page. Is that right? If so, it could do with
being included in the changelog.

On the other hand, can khugepaged be prevented from promoting a hugepage
because of KSM?

--
Mel Gorman
Part-time Phd Student Linux Technology Center
University of Limerick IBM Dublin Software Lab