On Wed, Dec 13, 2023 at 8:38 AM Dan Schatzberg <schatzberg.dan@xxxxxxxxx> wrote: > > On Tue, Dec 12, 2023 at 07:05:36PM -0700, Yu Zhao wrote: > > On Tue, Dec 12, 2023 at 6:39 PM Dan Schatzberg <schatzberg.dan@xxxxxxxxx> wrote: > > > > > > Allow proactive reclaimers to submit an additional swappiness=<val> > > > argument to memory.reclaim. This overrides the global or per-memcg > > > swappiness setting for that reclaim attempt. > > > > > > For example: > > > > > > echo "2M swappiness=0" > /sys/fs/cgroup/memory.reclaim > > > > > > will perform reclaim on the rootcg with a swappiness setting of 0 (no > > > swap) regardless of the vm.swappiness sysctl setting. > > > > > > Signed-off-by: Dan Schatzberg <schatzberg.dan@xxxxxxxxx> > > > > NAK. > > > > Please initialize new variables properly and test code changes > > thoroughly before submission. > > Could you be a bit more specific? The patch is compiling and working > locally but perhaps there's some configuration or behavior that I > haven't been testing. scan_control.swappiness is only initialized from try_to_free_mem_cgroup_pages(), which means that swappiness is now 0 for all other types of reclaim, which can be a huge problem. It might be easier to restore a special value (-1, 201, whatever) that means "use mem_cgroup_swappiness()".