On 6/10/19 2:36 PM, Oscar Salvador wrote:
On Tue, 2019-05-28 at 14:44 +0800, Yang Shi wrote:The commit 9092c71bb724 ("mm: use sc->priority for slab shrink targets") has broken up the relationship between sc->nr_scanned and slab pressure. The sc->nr_scanned can't double slab pressure anymore. So, it sounds no sense to still keep sc->nr_scanned inc'ed. Actually, it would prevent from adding pressure on slab shrink since excessive sc->nr_scanned would prevent from scan->priority raise.Hi Yang, I might be misunderstanding this, but did you mean "prevent from scan- priority decreasing"? I guess we are talking about balance_pgdat(), and in case kswapd_shrink_node() returns true (it means we have scanned more than we had to reclaim), raise_priority becomes false, and this does not let sc->priority to be decreased, which has the impact that less pages will be reclaimed the next round.
Yes, exactly.
Sorry for bugging here, I just wanted to see if I got this right.
