The patch "mm, vmscan: make shrink_node decisions more node-centric" checks whether compaction is suitable on empty nodes. This is expensive rather than wrong but is worth fixing.
This is a fix to the mmotm patch mm-vmscan-make-shrink_node-decisions-more-node-centric.patch Signed-off-by: Mel Gorman <[email protected]> --- mm/vmscan.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/mm/vmscan.c b/mm/vmscan.c index 864a3b1e5f8b..4fdb9e419588 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -2408,6 +2408,8 @@ static inline bool should_continue_reclaim(struct pglist_data *pgdat, /* If compaction would go ahead or the allocation would succeed, stop */ for (z = 0; z <= sc->reclaim_idx; z++) { struct zone *zone = &pgdat->node_zones[z]; + if (!populated_zone(zone)) + continue; switch (compaction_suitable(zone, sc->order, 0, sc->reclaim_idx)) { case COMPACT_PARTIAL: -- 2.6.4
