From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8DEDDC433F5 for ; Fri, 8 Oct 2021 13:55:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7900A60FD8 for ; Fri, 8 Oct 2021 13:55:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S242370AbhJHN5C (ORCPT ); Fri, 8 Oct 2021 09:57:02 -0400 Received: from outbound-smtp25.blacknight.com ([81.17.249.193]:56298 "EHLO outbound-smtp25.blacknight.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234113AbhJHN5B (ORCPT ); Fri, 8 Oct 2021 09:57:01 -0400 Received: from mail.blacknight.com (pemlinmail06.blacknight.ie [81.17.255.152]) by outbound-smtp25.blacknight.com (Postfix) with ESMTPS id 1B4E6CACD8 for ; Fri, 8 Oct 2021 14:55:05 +0100 (IST) Received: (qmail 8314 invoked from network); 8 Oct 2021 13:55:04 -0000 Received: from unknown (HELO stampy.112glenside.lan) (mgorman@techsingularity.net@[84.203.17.29]) by 81.17.254.9 with ESMTPA; 8 Oct 2021 13:55:04 -0000 From: Mel Gorman To: Linux-MM Cc: NeilBrown , Theodore Ts'o , Andreas Dilger , "Darrick J . Wong" , Matthew Wilcox , Michal Hocko , Dave Chinner , Rik van Riel , Vlastimil Babka , Johannes Weiner , Jonathan Corbet , Linux-fsdevel , LKML , Mel Gorman Subject: [PATCH 8/8] mm/vmscan: Delay waking of tasks throttled on NOPROGRESS Date: Fri, 8 Oct 2021 14:53:32 +0100 Message-Id: <20211008135332.19567-9-mgorman@techsingularity.net> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20211008135332.19567-1-mgorman@techsingularity.net> References: <20211008135332.19567-1-mgorman@techsingularity.net> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org 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%. Signed-off-by: Mel Gorman --- mm/vmscan.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/mm/vmscan.c b/mm/vmscan.c index 7b54fec4072c..80a9a26f701f 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -3338,8 +3338,11 @@ 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]; -- 2.31.1