Received: by 2002:a05:6a10:5bc5:0:0:0:0 with SMTP id os5csp1393181pxb; Thu, 28 Oct 2021 02:51:40 -0700 (PDT) X-Google-Smtp-Source: ABdhPJy+ftVFtzzOHDh9FT9803bOespUC21yzripr1H49BAgVsFVpTeJEwRk8rszs1wEFGm3ecV4 X-Received: by 2002:a05:6402:152:: with SMTP id s18mr4858865edu.356.1635414699972; Thu, 28 Oct 2021 02:51:39 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1635414699; cv=none; d=google.com; s=arc-20160816; b=fIYC8mpcj/urmqoFVoALOaWh2q5LoPZsU9u8LB/daH6FJ1Z2JHjFeLVZ2rEkyBB2hW tS2OqHDnbmf75laz4MG0Jh+4BiKoBFHZMdkE1RlECHAs0iU2sNU1PhxbatLtVD9aAGUR G5tG9zajjPZ5nAXsPlgHYEV7AwPOEFTxDBQTc8dRpz6M9sR/CV1oHnH+caEYYacWbIx4 sMAucIgxEsIxr9K09+z1p17Yi+GrfpJVpZjGOCKMF/ibba8ltBlHPZ69G4h3iawF0DFK TnhTGwnb3/YBEbnqGMqxFS0VsP/1UydnlShNCsRsE3FjDyEGtFlu6A1/2nuOr93DaMFR ZX1g== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:content-transfer-encoding:mime-version :message-id:date:subject:cc:to:from; bh=ZN29nSkBi6y56AeOCU2wv/8OE8jJ4MKFDwvl2/Bpq8M=; b=ut4hWjQMOEp3i7JYwEKRDSRilod2Kvq7rMA0W9arunH6nRXAhis7/QbJaEE4wMGj0B gUIROI5w/lIhXG/9dDxM32od511HVcTq1/n67LJD27qML1kdyaeBmzELtBMezdMlamTj uAzloOlsqoYl8bmQGoOufrvtM/rZTcHzPgZT4JXk/wj9ksE62PH8b1oU4FQKg5L/TSGB NcDXTLaM+g6siXVNaZSsrDDq0QV2tbMsfqImnGXweoVx5AgxIzGqjjsFkeU6Tw6yUH6C 24tcoePWO5ACYYZpbAIHpNx+4XDcGLYWLgw+wcVg9JNsvLQwRkZkwGMuCqF/itDEvbS+ 2UiA== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Return-Path: Received: from vger.kernel.org (vger.kernel.org. [23.128.96.18]) by mx.google.com with ESMTP id dm3si4245139ejc.220.2021.10.28.02.51.16; Thu, 28 Oct 2021 02:51:39 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18; Authentication-Results: mx.google.com; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229868AbhJ1Jv7 (ORCPT + 99 others); Thu, 28 Oct 2021 05:51:59 -0400 Received: from outbound-smtp22.blacknight.com ([81.17.249.190]:38621 "EHLO outbound-smtp22.blacknight.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230301AbhJ1Jve (ORCPT ); Thu, 28 Oct 2021 05:51:34 -0400 Received: from mail.blacknight.com (pemlinmail01.blacknight.ie [81.17.254.10]) by outbound-smtp22.blacknight.com (Postfix) with ESMTPS id 603C3BABC5 for ; Thu, 28 Oct 2021 10:48:45 +0100 (IST) Received: (qmail 22672 invoked from network); 28 Oct 2021 09:48:45 -0000 Received: from unknown (HELO stampy.112glenside.lan) (mgorman@techsingularity.net@[84.203.17.29]) by 81.17.254.9 with ESMTPA; 28 Oct 2021 09:48:45 -0000 From: Mel Gorman To: Peter Zijlstra Cc: Ingo Molnar , Vincent Guittot , Valentin Schneider , Aubrey Li , Barry Song , Mike Galbraith , Srikar Dronamraju , LKML , Mel Gorman Subject: [PATCH v4 0/2] Reduce stacking and overscheduling Date: Thu, 28 Oct 2021 10:48:32 +0100 Message-Id: <20211028094834.1312-1-mgorman@techsingularity.net> X-Mailer: git-send-email 2.31.1 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Also available at git://git.kernel.org/pub/scm/linux/kernel/git/mel/linux.git sched-scalewakegran-v4r1 Changelog since v3 o No code changes, added some additional results to patch 1 These series tackles two problems. The first is that heavy wakers can stack an excessive number of tasks on the same CPU. The second is that tasks can overschedule when the task has not reached its minimum preemption granularity. The patches are independent but were discussed together in the thread https://lore.kernel.org/r/20210920142614.4891-1-mgorman@techsingularity.net so are presented together. With both patches on a zen3 machine hackbench-process-pipes 5.15.0-rc3 5.15.0-rc3 vanilla sched-scalewakegran-v3r2 Amean 1 0.3667 ( 0.00%) 0.3823 ( -4.27%) Amean 4 0.5343 ( 0.00%) 0.4867 ( 8.92%) Amean 7 0.5300 ( 0.00%) 0.5053 ( 4.65%) Amean 12 0.5737 ( 0.00%) 0.5450 ( 5.00%) Amean 21 0.6727 ( 0.00%) 0.6807 ( -1.19%) Amean 30 0.8583 ( 0.00%) 0.7107 * 17.20%* Amean 48 1.3977 ( 0.00%) 1.0447 * 25.26%* Amean 79 1.9790 ( 0.00%) 1.6033 * 18.98%* Amean 110 2.8020 ( 0.00%) 2.0763 * 25.90%* Amean 141 3.6683 ( 0.00%) 2.5313 * 31.00%* Amean 172 4.6687 ( 0.00%) 3.1163 * 33.25%* Amean 203 5.2183 ( 0.00%) 3.5560 * 31.86%* Amean 234 6.1077 ( 0.00%) 3.8913 * 36.29%* Amean 265 7.1313 ( 0.00%) 4.2293 * 40.69%* Amean 296 7.7557 ( 0.00%) 4.5357 * 41.52%* 5.15.0-rc3 5.15.0-rc3 vanilla sched-scalewakegran-v3r2 Duration User 2933.05 2034.17 Duration System 25652.83 17137.08 Duration Elapsed 162.50 120.25 kernel/sched/fair.c | 27 ++++++++++++++++++++++++--- kernel/sched/features.h | 2 ++ 2 files changed, 26 insertions(+), 3 deletions(-) -- 2.31.1