Re: [PATCH 13/35] autonuma: add page structure fields

Rik van Riel
2012-05-29T13:57:36Z

On 05/29/2012 09:16 AM, Peter Zijlstra wrote:
> On Fri, 2012-05-25 at 19:02 +0200, Andrea Arcangeli wrote:

> 24 bytes per page.. or ~0.6% of memory gone. This is far too great a
> price to pay.
>
> At LSF/MM Rik already suggested you limit the number of pages that can
> be migrated concurrently and use this to move the extra list_head out of
> struct page and into a smaller amount of extra structures, reducing the
> total overhead.

For THP, we should be able to track this NUMA info on a
2MB page granularity.

It is not like we will ever want to break up a large
page into small pages anyway (with different 4kB pages
going to different NUMA nodes), because the THP benefit
is on the same order of magnitude as the NUMA benefit.

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