On Wed, 13 Oct 2010 10:36:53 +0200 Andi Kleen <andi@xxxxxxxxxxxxxx> wrote: > KAMEZAWA Hiroyuki <kamezawa.hiroyu@xxxxxxxxxxxxxx> writes: > > >> > My intention is not for allocating HUGEPAGE(> MAX_ORDER). > >> > >> I still believe using this for 1GB pages would be one of the more > >> interesting use cases. > >> > > > > I'm successfully allocating 1GB of continous pages at test. But I'm not sure > > requirements and users. How quick this allocation should be ? > > This will always be slow. Huge pages are always pre allocated > even today through a sysctl. The use case would be have > > echo XXX > /proc/sys/vm/nr_hugepages > > at runtime working for 1GB too, instead of requiring a reboot > for this. > > I think it's ok if that is somewhat slow, as long as it is not > incredible slow. Ideally it shouldn't cause a swap storm either > > (maybe we need some way to indicate how hard the freeing code should > try?) > yes. I think this patch should be update to do a precice control of memory pressure. It will improve memory hotplug's memory allocation, too. > I guess it would only really work well if you predefine > movable zones at boot time. > I think so, too. But maybe enough for embeded guys and very special systems which need to use 1G page. 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/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>