On 10/11/2011 03:55 PM, Andrew Morton wrote: > On Tue, 11 Oct 2011 15:32:11 -0400 > Satoru Moriya <satoru.moriya@xxxxxxx> wrote: > >> On 10/10/2011 06:37 PM, Andrew Morton wrote: >>> On Fri, 7 Oct 2011 20:08:19 -0700 (PDT) David Rientjes >>> <rientjes@xxxxxxxxxx> wrote: >>> >>>> On Thu, 1 Sep 2011, Rik van Riel wrote: >> >> Actually page allocator decreases min watermark to 3/4 * min >> watermark for rt-task. But in our case some applications create a lot >> of processes and if all of them are rt-task, the amount of watermark >> bonus(1/4 * min watermark) is not enough. >> >> If we can tune the amount of bonus, it may be fine. But that is >> almost all same as extra free kbytes. > > This situation is detectable at runtime. If realtime tasks are being > stalled in the page allocator then start to increase the free-page > reserves. A little control system. Detecting at runtime is too late for some latency critical systems. At that system, we must avoid a stall before it happens. Also, if we increase the free-page reserves a.k.a min_free_kbytes, the possibility of direct reclaim on other workloads increases. I think it's a bad side effect. Thanks, Satoru -- 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/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: <a href