On Wed, Apr 25, 2018 at 09:19:29AM +0530, Vijayanand Jitta wrote: > >>>> Idk, I don't like the idea of adding a counter outside of the vm counters > >>>> infrastructure, and I definitely wouldn't touch the exposed > >>>> nr_slab_reclaimable and nr_slab_unreclaimable fields. > >>> > >>> We would be just making the reported values more precise wrt reality. > >> > >> It depends on if we believe that only slab memory can be reclaimable > >> or not. If yes, this is true, otherwise not. > >> > >> My guess is that some drivers (e.g. networking) might have buffers, > >> which are reclaimable under mempressure, and are allocated using > >> the page allocator. But I have to look closer... > >> > > > > One such case I have encountered is that of the ION page pool. The page pool > > registers a shrinker. When not in any memory pressure page pool can go high > > and thus cause an mmap to fail when OVERCOMMIT_GUESS is set. I can send > > a patch to account ION page pool pages in NR_INDIRECTLY_RECLAIMABLE_BYTES. Perfect! This is exactly what I've expected. > > > > Thanks, > > Vinayak > > > > As Vinayak mentioned NR_INDIRECTLY_RECLAIMABLE_BYTES can be used to solve the issue > with ION page pool when OVERCOMMIT_GUESS is set, the patch for the same can be > found here https://lkml.org/lkml/2018/4/24/1288 This makes perfect sense to me. Please, fell free to add: Acked-by: Roman Gushchin <guro@xxxxxx> Thank you!
