On Sun 26-01-20 11:53:55, Cong Wang wrote: > On Tue, Jan 21, 2020 at 1:00 AM Michal Hocko <mhocko@xxxxxxxxxx> wrote: > > > > On Mon 20-01-20 14:48:05, Cong Wang wrote: > > > It got stuck somewhere along the call path of mem_cgroup_try_charge(), > > > and the trace events of mm_vmscan_lru_shrink_inactive() indicates this > > > too: > > > > So it seems that you are condending on the page lock. It is really > > unexpected that the reclaim would take that long though. Please try to > > enable more vmscan tracepoints to see where the time is spent. > > Sorry for the delay. I have been trying to collect more data in one shot. > > This is a a typical round of the loop after enabling all vmscan tracepoints: > > <...>-455450 [007] .... 4048595.842992: > mm_vmscan_memcg_reclaim_begin: order=0 may_writepage=1 > gfp_flags=GFP_NOFS|__GFP_HIGHMEM|__GFP_HARDWALL|__GFP_MOVABLE > classzone_idx=4 > <...>-455450 [007] .... 4048595.843012: > mm_vmscan_memcg_reclaim_end: nr_reclaimed=0 This doesn't tell us much though. This reclaim round has taken close to no time. See timestamps. > The whole trace output is huge (33M), I can provide it on request. Focus on reclaim rounds that take a long time and see where it gets you. -- Michal Hocko SUSE Labs
