On Thu, 2010-03-11 at 10:17 +0900, KAMEZAWA Hiroyuki wrote: > On Thu, 11 Mar 2010 09:39:13 +0900 > KAMEZAWA Hiroyuki <kamezawa.hiroyu@xxxxxxxxxxxxxx> wrote: > > > The performance overhead is not so huge in both solutions, but the impact on > > > performance is even more reduced using a complicated solution... > > > > > > Maybe we can go ahead with the simplest implementation for now and start to > > > think to an alternative implementation of the page_cgroup locking and > > > charge/uncharge of pages. FWIW bit spinlocks suck massive. > > > > maybe. But in this 2 years, one of our biggest concerns was the performance. > > So, we do something complex in memcg. But complex-locking is , yes, complex. > > Hmm..I don't want to bet we can fix locking scheme without something complex. > > > But overall patch set seems good (to me.) And dirty_ratio and dirty_background_ratio > will give us much benefit (of performance) than we lose by small overheads. Well, the !cgroup or root case should really have no performance impact. > IIUC, this series affects trgger for background-write-out. Not sure though, while this does the accounting the actual writeout is still !cgroup aware and can definately impact performance negatively by shrinking too much. -- 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/ . Don't email: <a href