On Thu 05-04-18 17:05:39, Joonsoo Kim wrote: > On Thu, Apr 05, 2018 at 09:57:53AM +0200, Michal Hocko wrote: > > On Thu 05-04-18 16:27:16, Joonsoo Kim wrote: > > > From: Joonsoo Kim <iamjoonsoo.kim@xxxxxxx> > > > > > > ZONE_MOVABLE only has movable pages so we don't need to keep enough > > > freepages to avoid or deal with fragmentation. So, don't count it. > > > > > > This changes min_free_kbytes and thus min_watermark greatly > > > if ZONE_MOVABLE is used. It will make the user uses more memory. > > > > OK, but why does it matter. Has anybody seen this as an issue? > > There was a regression report for CMA patchset and I think that it is > related to this problem. CMA patchset makes the system uses one more > zone (ZONE_MOVABLE) and then increase min_free_kbytes. It reduces > usable memory and it could cause regression. > > http://lkml.kernel.org/r/20180102063528.GG30397@yexl-desktop Then this should be a part of the changelog along with some reproducible results, please. -- Michal Hocko SUSE Labs
