From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-ot1-f48.google.com (mail-ot1-f48.google.com [209.85.210.48]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 4045617540 for ; Fri, 12 Jan 2024 16:58:30 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linaro.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linaro.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=linaro.org header.i=@linaro.org header.b="qaWX86vl" Received: by mail-ot1-f48.google.com with SMTP id 46e09a7af769-6dc36e501e1so4571686a34.1 for ; Fri, 12 Jan 2024 08:58:30 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; t=1705078710; x=1705683510; darn=vger.kernel.org; h=cc:to:subject:message-id:date:from:in-reply-to:references :mime-version:from:to:cc:subject:date:message-id:reply-to; bh=u+lQGn74TGq7hrOXT4TkI+kQ8ytJDBxjKrUJkE5tzl4=; b=qaWX86vlJlNHKDapvCjUIJO13Fb2vfor+fqeSrXYleqqEjUBux4pDDQ8QtY/bCXnjG 1e2DAyJPjvAdtcShn14coOIIqHgYVJGENXmLEtPMGnDSI093N8cPpYOXdNpCZlkKl69P T//1B4x6ldVbV7mgWvCeaQQvCoTCJtYpOLa3ileVnHQ6UikdZHm4mbP7GO+L27PIWJb8 LmCLnhVpr1gJ+xKfjhk2/uLDcyihV65wlMYwPayusKP1Y2A6Ocayg8GHh6I1HLLeUrnl BKaxLYMjZCVBAsTf7MBQc/0JvB7ZxZB07INL+ZMSrYoCm5uACzobz47vhQzzK+UdGOPU UnSA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1705078710; x=1705683510; h=cc:to:subject:message-id:date:from:in-reply-to:references :mime-version:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=u+lQGn74TGq7hrOXT4TkI+kQ8ytJDBxjKrUJkE5tzl4=; b=JUYtXfuPGAR/0XfhJCatu/CHuqRTg3fbhfFb/wXD4JnDiUKlGj3LZIyTTKBIeylaZH cDJglFs4iW+sfg2R4tpWdw465kTvfUo4E3yJKBaUtsTcgi96xGRepJ5ZJlvobw5+YphU OlVZKmrPCIViK23vwZPjsGejD2HUEyGEhnDktE5zI72yZAKTH6eG6DnvIxU0frYk7PTh eCrRx5VvCyzRHfrZrzhMtQeEBMQroaw/pcPP+1bwYq1ob4CsnI1gEOmV8Mv9VkGtlsa7 KyL67LKkxmuGZIwBVk37VOR4mOelHxHbVHUyXtH+/xlojlN9rtwHTU1ZuYBckfyNICP2 cqaw== X-Gm-Message-State: AOJu0YzW8gvyEtvHU1VfSpRpn2GRPYG9YYs3k0jG5xzW3rx0jhVhhv5t iPBOHw3SuFerGxKi0ZhlXx9lcRARhe+JSBkLIPgcDNEDGSi7sQ== X-Google-Smtp-Source: AGHT+IFSJ+4kv5Xs/qSCOHlxXtVL+bWi6OI4MLczYE6LXm3MNhlMW9aCl25vEmTgGsslYr0h2HnoONvX8TJ6FfWASaM= X-Received: by 2002:a05:6358:917:b0:175:97b6:af54 with SMTP id r23-20020a056358091700b0017597b6af54mr2046614rwi.15.1705078710054; Fri, 12 Jan 2024 08:58:30 -0800 (PST) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 References: <4405adb5-0b16-4716-9542-47d8bb1737ee@arm.com> In-Reply-To: <4405adb5-0b16-4716-9542-47d8bb1737ee@arm.com> From: Vincent Guittot Date: Fri, 12 Jan 2024 17:58:18 +0100 Message-ID: Subject: Re: [GIT PULL] Scheduler changes for v6.8 To: Dietmar Eggemann Cc: Linus Torvalds , Ingo Molnar , linux-kernel@vger.kernel.org, Peter Zijlstra , Thomas Gleixner , Juri Lelli , Steven Rostedt , Ben Segall , Mel Gorman , Daniel Bristot de Oliveira , Valentin Schneider Content-Type: text/plain; charset="UTF-8" On Fri, 12 Jan 2024 at 15:23, Dietmar Eggemann wrote: > > On 11/01/2024 19:16, Vincent Guittot wrote: > > On Thu, 11 Jan 2024 at 18:53, Linus Torvalds > > wrote: > >> > >> On Thu, 11 Jan 2024 at 09:45, Linus Torvalds > >> wrote: > >>> > >>> On Thu, 11 Jan 2024 at 00:11, Vincent Guittot > >>> wrote: > >>>> > >>>> Could you confirm that cpufreq governor is schedutil and the driver is > >>>> amd-pstate on your system ? > >>> > >>> schedutil yes, amd-pstate no. I actually just use acpi_cpufreq > >> > >> Bah. Hit 'send' mistakenly too soon, thus the abrupt end and > >> unfinished quoting removal. > >> > >> And don't ask me why it's acpi_pstate-driven. I have X86_AMD_PSTATE=y, but > >> > >> /sys/devices/system/cpu/cpufreq/policy0/scaling_driver > >> > >> clearly says 'acpi-cpufreq'. Maybe I'm looking in the wrong place. My dmesg says > > > > That seems to be the right place to look > > > >> > >> amd_pstate: the _CPC object is not present in SBIOS or ACPI disabled > >> > >> which is presumably the reason my machine uses acpi-pstate. > >> > >> I will also test out your other questions, but I need to go back and > >> do more pull requests first. > > > > ok, thanks > > > > I'm going to continue checking what else could trigger such regression > > having in mind that your system should not have beeb impacted by this > > changes > > I can't see the regression on my > > 20-core (40-thread) Intel Xeon CPU E5-2690 v2 > > with 'schedutil' and 'acpi-cpufreq'. Thanks for the tests > > f12560779f9d - sched/cpufreq: Rework iowait boost <- (w/ patches) > 9c0b4bb7f630 - sched/cpufreq: Rework schedutil governor performance estimation > 50181c0cff31 - sched/pelt: Avoid underestimation of task utilization <- (base) > ... > > # cpufreq-info -c 0 -e > ... > analyzing CPU 0: > driver: acpi-cpufreq > CPUs which run at the same hardware frequency: 0 > CPUs which need to have their frequency coordinated by software: 0 > maximum transition latency: 10.0 us. > hardware limits: 1.20 GHz - 3.00 GHz > available frequency steps: 3.00 GHz, 3.00 GHz, 2.90 GHz, 2.70 GHz, 2.60 GHz, 2.50 GHz, 2.40 GHz, 2.20 GHz, > 2.10 GHz, 2.00 GHz, 1.80 GHz, 1.70 GHz, 1.60 GHz, 1.50 GHz, 1.30 GHz, 1.20 GHz > available cpufreq governors: conservative, ondemand, userspace, powersave, performance, schedutil > current policy: frequency should be within 1.20 GHz and 3.00 GHz. > The governor "schedutil" may decide which speed to use > within this range. > current CPU frequency is 1.20 GHz (asserted by call to hardware). > > > cpufreq is still fast-switching, so no schedutil 'sugov' DL threads.