On Tue, 25 Feb 2020 14:30:03 -0800 Shakeel Butt wrote:
>
> BTW we are seeing a similar situation in our production environment.
> We have swappiness=0, no swap from kswapd (because we don't swapout on
> pressure, only on cold age) and too few file pages, the kswapd goes
> crazy on shrink_slab and spends 100% cpu on it.
Dunno if swappiness is able to put peace on your kswapd.
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -2631,8 +2631,14 @@ static inline bool should_continue_recla
*/
pages_for_compaction = compact_gap(sc->order);
inactive_lru_pages = node_page_state(pgdat, NR_INACTIVE_FILE);
- if (get_nr_swap_pages() > 0)
- inactive_lru_pages += node_page_state(pgdat, NR_INACTIVE_ANON);
+ do {
+ struct lruvec *lruvec = mem_cgroup_lruvec(sc->target_mem_cgroup, pgdat);
+ struct mem_cgroup *memcg = lruvec_memcg(lruvec);
+ int swappiness = mem_cgroup_swappiness(memcg);
+
+ if (swappiness && get_nr_swap_pages() > 0)
+ inactive_lru_pages += node_page_state(pgdat, NR_INACTIVE_ANON);
+ } while (0);
return inactive_lru_pages > pages_for_compaction;
}
