On Wed, Dec 8, 2010 at 10:56 AM, KAMEZAWA Hiroyuki <kamezawa.hiroyu@xxxxxxxxxxxxxx> wrote: > 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. Yes, I thought that, too. I think it would be a good feature in embedded system. > > - kvictimed? will move unmappedd page caches to victim list > This may work like a InactiveClean list which we had before and make > sizing easy. > Before further discuss, we need customer's confirm. We know very well it is very hard to merge if anyone doesn't use. Balbir, What do think about it? > Thanks, > -Kame > > > > -- Kind regards, Minchan Kim -- 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>