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 X-Spam-Level: X-Spam-Status: No, score=-10.4 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT,USER_IN_DEF_DKIM_WL autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id BF8CAC48BD7 for ; Thu, 27 Jun 2019 19:49:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 9A80B20665 for ; Thu, 27 Jun 2019 19:49:41 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=indeed.com header.i=@indeed.com header.b="NCZODYSj" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726513AbfF0Ttk (ORCPT ); Thu, 27 Jun 2019 15:49:40 -0400 Received: from mail-oi1-f171.google.com ([209.85.167.171]:34170 "EHLO mail-oi1-f171.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726465AbfF0Ttj (ORCPT ); Thu, 27 Jun 2019 15:49:39 -0400 Received: by mail-oi1-f171.google.com with SMTP id l12so2506005oil.1 for ; Thu, 27 Jun 2019 12:49:39 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=indeed.com; s=google; h=from:to:subject:date:message-id:in-reply-to:references; bh=AesOW3EmeuBjZTWgdRCKfU4DW0QAsRu61r3/LGTQTg8=; b=NCZODYSjpvpfxj59czkgru2M6MbuOf355ojoS6qv35oesf0ZPEKewPbzf8Q6hUTwNZ 63GC9qzntLhV3BXxzsA1wfMonAydRnckvGu7+Ty6+pC2zHJpo0wDteG4b3WNGiac6WEN get4j9BzPfJbNVLnEdYRJcAD/bpv4qOuVvgK4= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:subject:date:message-id:in-reply-to :references; bh=AesOW3EmeuBjZTWgdRCKfU4DW0QAsRu61r3/LGTQTg8=; b=DF3lzNK60q8e476vlqZN1KKm1jsOLuG0D4z0XqDxzh158ibJwM69YWFBQi1mii2GVq HOB2OAvJafjhT0z5wUQ6qq2CTgW/vHGoedPAW5X3j8JA4ItfE+GBQ2Mu5TLx5hGDLd1Q NnmJLKL7tQITzTnH4WZN4AMEttzdmmJDgVfj4wF+wOj1BvHIAzBNQWNXYm0ZxHdiOGT4 gM8cFTTz7vo38U+0uWrfOXf//vcHclO86GmOmw3xW1fic6sJqWlYWPUpwDhn1teAGZ16 LFa+DKZpDGbCH1zxS8v2p3ckzHt3o0rvBfgP2YCZLmnu4cNS5BAYmViAP5nkeENnA0+Z iwoQ== X-Gm-Message-State: APjAAAVQRn9p9lqVIQ61JvMTyxvuEUHvb+4JLJ2Gu34RqX4z3MsKw7ln UJ5/3vAHnjeXxGeAXin3O8nwtQ== X-Google-Smtp-Source: APXvYqyVAP6KFgB2RBp3IQGLzuIHqYp8k5AhEcsIAc1tToG/shUzilO1cd2B6XGEl8mHP2WOzj0kvQ== X-Received: by 2002:aca:cfd0:: with SMTP id f199mr3076083oig.50.1561664978390; Thu, 27 Jun 2019 12:49:38 -0700 (PDT) Received: from cando.ausoff.indeed.net ([97.105.47.162]) by smtp.gmail.com with ESMTPSA id d200sm1148032oih.26.2019.06.27.12.49.37 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 27 Jun 2019 12:49:37 -0700 (PDT) From: Dave Chiluk To: Ben Segall , Pqhil Auld , Peter Oskolkov , Peter Zijlstra , Ingo Molnar , cgroups@vger.kernel.org, linux-kernel@vger.kernel.org, Brendan Gregg , Kyle Anderson , Gabriel Munos , John Hammond , Cong Wang , Jonathan Corbet , linux-doc@vger.kernel.org Subject: [PATCH v5 0/1] sched/fair: Fix low cpu usage with high throttling by removing expiration of cpu-local slices Date: Thu, 27 Jun 2019 14:49:29 -0500 Message-Id: <1561664970-1555-1-git-send-email-chiluk+linux@indeed.com> X-Mailer: git-send-email 1.8.3.1 In-Reply-To: <1558121424-2914-1-git-send-email-chiluk+linux@indeed.com> References: <1558121424-2914-1-git-send-email-chiluk+linux@indeed.com> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Changelog v5 - Based on this comment from Ben Segall's comment on v4 > If the cost of taking this global lock across all cpus without a > ratelimit was somehow not a problem, I'd much prefer to just set > min_cfs_rq_runtime = 0. (Assuming it is, I definitely prefer the "lie > and sorta have 2x period 2x runtime" solution of removing expiration) I'm resubmitting my v3 patchset, with the requested changes. - Updated Commit log given review comments - Update sched-bwc.txt give my new understanding of the slack timer. Changelog v4 - Rewrote patchset around the concept of returning all of runtime_remaining when cfs_b nears the end of available quota. Changelog v3 - Reworked documentation to better describe behavior of slice expiration per feedback from Peter Oskolkov Changelog v2 - Fixed some checkpatch errors in the commit message.