From patchwork Tue Oct 19 09:01:08 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mel Gorman X-Patchwork-Id: 12569191 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 C4A73C433F5 for ; Tue, 19 Oct 2021 09:02:43 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 7826A6115A for ; Tue, 19 Oct 2021 09:02:43 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 7826A6115A Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=techsingularity.net Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kvack.org Received: by kanga.kvack.org (Postfix) id 1F3DF6B007E; Tue, 19 Oct 2021 05:02:43 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 1A4006B0080; Tue, 19 Oct 2021 05:02:43 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 093346B0081; Tue, 19 Oct 2021 05:02:43 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0153.hostedemail.com [216.40.44.153]) by kanga.kvack.org (Postfix) with ESMTP id EF49E6B007E for ; Tue, 19 Oct 2021 05:02:42 -0400 (EDT) Received: from smtpin11.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay04.hostedemail.com (Postfix) with ESMTP id AF99931EDF for ; Tue, 19 Oct 2021 09:02:42 +0000 (UTC) X-FDA: 78712596564.11.0305F97 Received: from outbound-smtp16.blacknight.com (outbound-smtp16.blacknight.com [46.22.139.233]) by imf21.hostedemail.com (Postfix) with ESMTP id A2C1DD042B68 for ; Tue, 19 Oct 2021 09:02:40 +0000 (UTC) Received: from mail.blacknight.com (pemlinmail01.blacknight.ie [81.17.254.10]) by outbound-smtp16.blacknight.com (Postfix) with ESMTPS id 161491C55D2 for ; Tue, 19 Oct 2021 10:02:41 +0100 (IST) Received: (qmail 10926 invoked from network); 19 Oct 2021 09:02:40 -0000 Received: from unknown (HELO stampy.112glenside.lan) (mgorman@techsingularity.net@[84.203.17.29]) by 81.17.254.9 with ESMTPA; 19 Oct 2021 09:02:40 -0000 From: Mel Gorman To: Andrew Morton 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-MM , Linux-fsdevel , LKML , Mel Gorman Subject: [PATCH 8/8] mm/vmscan: Delay waking of tasks throttled on NOPROGRESS Date: Tue, 19 Oct 2021 10:01:08 +0100 Message-Id: <20211019090108.25501-9-mgorman@techsingularity.net> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20211019090108.25501-1-mgorman@techsingularity.net> References: <20211019090108.25501-1-mgorman@techsingularity.net> MIME-Version: 1.0 X-Stat-Signature: thkwrdjtsi3rs3gj57cx9ku9c54nnp6q Authentication-Results: imf21.hostedemail.com; dkim=none; spf=pass (imf21.hostedemail.com: domain of mgorman@techsingularity.net designates 46.22.139.233 as permitted sender) smtp.mailfrom=mgorman@techsingularity.net; dmarc=none X-Rspamd-Server: rspam04 X-Rspamd-Queue-Id: A2C1DD042B68 X-HE-Tag: 1634634160-122776 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: 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 Acked-by: Vlastimil Babka --- mm/vmscan.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) diff --git a/mm/vmscan.c b/mm/vmscan.c index ec2006680242..28adc196353d 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -1057,7 +1057,7 @@ void reclaim_throttle(pg_data_t *pgdat, enum vmscan_throttle_state reason) ret = schedule_timeout(timeout); finish_wait(wqh, &wait); - if (reason == VMSCAN_THROTTLE_ISOLATED) + if (reason == VMSCAN_THROTTLE_WRITEBACK) atomic_dec(&pgdat->nr_writeback_throttled); trace_mm_vmscan_throttled(pgdat->node_id, jiffies_to_usecs(timeout), @@ -3349,8 +3349,11 @@ 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];