Re: [PATCH 5/5] mm, vmscan: Account for skipped pages as a partial scan

From: Johannes Weiner
Date: Fri Jul 22 2016 - 12:02:23 EST


On Thu, Jul 21, 2016 at 03:11:01PM +0100, Mel Gorman wrote:
> Page reclaim determines whether a pgdat is unreclaimable by examining how
> many pages have been scanned since a page was freed and comparing that to
> the LRU sizes. Skipped pages are not reclaim candidates but contribute to
> scanned. This can prematurely mark a pgdat as unreclaimable and trigger
> an OOM kill.
>
> This patch accounts for skipped pages as a partial scan so that an
> unreclaimable pgdat will still be marked as such but by scaling the cost
> of a skip, it'll avoid the pgdat being marked prematurely.
>
> Signed-off-by: Mel Gorman <mgorman@xxxxxxxxxxxxxxxxxxx>

Acked-by: Johannes Weiner <hannes@xxxxxxxxxxx>