* KOSAKI Motohiro <kosaki.motohiro@xxxxxxxxxxxxxx> [2011-04-01 16:56:57]: > Hi > > > > 1) zone reclaim doesn't work if the system has multiple node and the > > > workload is file cache oriented (eg file server, web server, mail server, et al). > > > because zone recliam make some much free pages than zone->pages_min and > > > then new page cache request consume nearest node memory and then it > > > bring next zone reclaim. Then, memory utilization is reduced and > > > unnecessary LRU discard is increased dramatically. > > > > > > SGI folks added CPUSET specific solution in past. (cpuset.memory_spread_page) > > > But global recliam still have its issue. zone recliam is HPC workload specific > > > feature and HPC folks has no motivation to don't use CPUSET. > > > > I am afraid you misread the patches and the intent. The intent to > > explictly enable control of unmapped pages and has nothing > > specifically to do with multiple nodes at this point. The control is > > system wide and carefully enabled by the administrator. > > Hm. OK, I may misread. > Can you please explain the reason why de-duplication feature need to selectable and > disabled by defaut. "explicity enable" mean this feature want to spot corner case issue?? > Yes, because given a selection of choices (including what you mentioned in the review), it would be nice to have this selectable. -- Three Cheers, Balbir -- 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 internet charges in Canada: sign http://stopthemeter.ca/ Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>