Commit 66ce520b authored by Mel Gorman's avatar Mel Gorman Committed by Linus Torvalds
Browse files

mm/vmscan: delay waking of tasks throttled on NOPROGRESS 

Tracing indicates that tasks throttled on NOPROGRESS are woken
prematurely resulting in occasional massive spikes in direct reclaim
activity.  This patch wakes tasks throttled on NOPROGRESS if reclaim
efficiency is at least 12%.

Link: https://lkml.kernel.org/r/20211022144651.19914-9-mgorman@techsingularity.net


Signed-off-by: default avatarMel Gorman <mgorman@techsingularity.net>
Acked-by: default avatarVlastimil Babka <vbabka@suse.cz>
Cc: Andreas Dilger <adilger.kernel@dilger.ca>
Cc: "Darrick J . Wong" <djwong@kernel.org>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: NeilBrown <neilb@suse.de>
Cc: Rik van Riel <riel@surriel.com>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent a19594ca

mm/vmscan.c

+5 −2
Original line number Diff line number Diff line
@@ -3348,8 +3348,11 @@ static inline bool compaction_ready(struct zone *zone, struct scan_control *sc) 


static void consider_reclaim_throttle(pg_data_t *pgdat, struct scan_control *sc)

{

	/* If reclaim is making progress, wake any throttled tasks. */

	if (sc->nr_reclaimed) {

	/*

	 * If reclaim is making progress greater than 12% efficiency then

	 * wake all the NOPROGRESS throttled tasks.

	 */

	if (sc->nr_reclaimed > (sc->nr_scanned >> 3)) {

		wait_queue_head_t *wqh;



		wqh = &pgdat->reclaim_wait[VMSCAN_THROTTLE_NOPROGRESS];