On Mon, Dec 26, 2016 at 01:48:40PM +0100, Michal Hocko wrote: > On Fri 23-12-16 23:26:00, Nils Holland wrote: > > On Fri, Dec 23, 2016 at 03:47:39PM +0100, Michal Hocko wrote: > > > > > > Nils, even though this is still highly experimental, could you give it a > > > try please? > > > > Yes, no problem! So I kept the very first patch you sent but had to > > revert the latest version of the debugging patch (the one in > > which you added the "mm_vmscan_inactive_list_is_low" event) because > > otherwise the patch you just sent wouldn't apply. Then I rebooted with > > memory cgroups enabled again, and the first thing that strikes the eye > > is that I get this during boot: > > > > [ 1.568174] ------------[ cut here ]------------ > > [ 1.568327] WARNING: CPU: 0 PID: 1 at mm/memcontrol.c:1032 mem_cgroup_update_lru_size+0x118/0x130 > > [ 1.568543] mem_cgroup_update_lru_size(f4406400, 2, 1): lru_size 0 but not empty > > Ohh, I can see what is wrong! a) there is a bug in the accounting in > my patch (I double account) and b) the detection for the empty list > cannot work after my change because per node zone will not match per > zone statistics. The updated patch is below. So I hope my brain already > works after it's been mostly off last few days... > --- > From 397adf46917b2d9493180354a7b0182aee280a8b Mon Sep 17 00:00:00 2001 > From: Michal Hocko <mhocko@xxxxxxxx> > Date: Fri, 23 Dec 2016 15:11:54 +0100 > Subject: [PATCH] mm, memcg: fix the active list aging for lowmem requests when > memcg is enabled > > Nils Holland has reported unexpected OOM killer invocations with 32b > kernel starting with 4.8 kernels > I think it's unfortunate that per-zone stats are reintroduced to the memcg structure. I can't help but think that it would have also worked to always rotate a small number of pages if !inactive_list_is_low and reclaiming for memcg even if it distorted page aging. However, given that such an approach would be less robust and this has been heavily tested; Acked-by: Mel Gorman <mgorman@xxxxxxx> -- Mel Gorman SUSE Labs -- 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/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>