On Wed, Aug 18, 2021 at 8:26 AM Johannes Weiner <hannes@xxxxxxxxxxx> wrote: > > In a debugging session the other day, Rik noticed that node_reclaim() > was missing memstall annotations. This means we'll miss pressure and > lost productivity resulting from reclaim on an overloaded local NUMA > node when vm.zone_reclaim_mode is enabled. > > There haven't been any reports, but that's likely because > vm.zone_reclaim_mode hasn't been a commonly used feature recently, and > the intersection between such setups and psi users is probably > nil. Although, secondary memory such as CXL-connected DIMMS, > persistent memory etc. and the page demotion patches that handle them > (https://lore.kernel.org/lkml/20210401183216.443C4443@xxxxxxxxxxxxxxxxxx/) > could soon make this a more common codepath again. > > Reported-by: Rik van Riel <riel@xxxxxxxxxxx> > Signed-off-by: Johannes Weiner <hannes@xxxxxxxxxxx> Reviewed-by: Shakeel Butt <shakeelb@xxxxxxxxxx>
