On Wed, 8 Dec 2010 10:43:08 +0900 Minchan Kim <minchan.kim@xxxxxxxxx> wrote: > Hi Kame, > Hi, > > I wonder ...how about adding "victim" list for "Reclaim" pages ? Then, we don't need > > extra LRU rotation. > > It can make the code clean. > As far as I think, victim list does following as. > > 1. select victim pages by strong hint > 2. move the page from LRU to victim > 3. reclaimer always peeks victim list before diving into LRU list. > 4-1. If the victim pages is used by others or dirty, it can be moved > into LRU, again or remain the page in victim list. > If the page is remained victim, when do we move it into LRU again if > the reclaimer continues to fail the page? When sometone touches it. > We have to put the new rule. > 4-2. If the victim pages isn't used by others and clean, we can > reclaim the page asap. > > AFAIK, strong hints are just two(invalidation, readahead max window heuristic). > I am not sure it's valuable to add new hierarchy(ie, LRU, victim, > unevictable) for cleaning the minor codes. > In addition, we have to put the new rule so it would make the LRU code > complicated. > I remember how unevictable feature merge is hard. > yes, it was hard. > But I am not against if we have more usecases. In this case, it's > valuable to implement it although it's not easy. > I wonder "victim list" can be used for something like Cleancache, when we have very-low-latency backend devices. And we may able to have page-cache-limit, which Balbir proposed as. - kvictimed? will move unmappedd page caches to victim list This may work like a InactiveClean list which we had before and make sizing easy. Thanks, -Kame -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxxx For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom policy in Canada: sign http://dissolvethecrtc.ca/ Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>