On 01/10/2014 01:10 PM, Johannes Weiner wrote: > This patch solves one half of the problem by decoupling the ability to > detect working set changes from the inactive list size. By > maintaining a history of recently evicted file pages it can detect > frequently used pages with an arbitrarily small inactive list size, > and subsequently apply pressure on the active list based on actual > demand for cache, not just overall eviction speed. > > Every zone maintains a counter that tracks inactive list aging speed. > When a page is evicted, a snapshot of this counter is stored in the > now-empty page cache radix tree slot. On refault, the minimum access > distance of the page can be assessed, to evaluate whether the page > should be part of the active list or not. > > This fixes the VM's blindness towards working set changes in excess of > the inactive list. And it's the foundation to further improve the > protection ability and reduce the minimum inactive list size of 50%. > > Signed-off-by: Johannes Weiner <hannes@xxxxxxxxxxx> Reviewed-by: Rik van Riel <riel@xxxxxxxxxx> -- All rights reversed -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>