From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 50EE579EA for ; Mon, 2 Dec 2024 13:52:52 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.140.110.172 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1733147576; cv=none; b=beDLvas01D7kfc58x0sIDU1r8ftTtoma6R4B2otSDo8xgSh5L17avEz6cKzLxpoW9PSUkN4iVkM0tHI6REwUAWBMS0c4NXFMFMF4jPskiNexCK0uhqSIa2wBaV/+c/zrO4RMgmw+cu7Qm6X41vIljPxWSzDvA+qrMCpl/Hj3mIM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1733147576; c=relaxed/simple; bh=/vYsJHI9CuPDtXQ/XxKYlO1C14RTfWm6TWI6cI62aA8=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=nB6S1bcjwts5ViisZh4XpF0pbvHrDLfsmyv1rIEM4xrmByYPESnAOujAkt2uzI+40bTqhnk/XqVN+H5xalw+ygG3KRkNEE/N5hc2Rar9cD4f9yilTHrO9zcDIfvgJHcMc8UVn2+xanvfvpYe6v+3J9150Z45AGxJZELFzFcwY94= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com; spf=pass smtp.mailfrom=arm.com; arc=none smtp.client-ip=217.140.110.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=arm.com Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id C61631007; Mon, 2 Dec 2024 05:53:20 -0800 (PST) Received: from [192.168.178.6] (usa-sjc-mx-foss1.foss.arm.com [172.31.20.19]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 79B303F58B; Mon, 2 Dec 2024 05:52:50 -0800 (PST) Message-ID: Date: Mon, 2 Dec 2024 14:52:41 +0100 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH 0/10 v2] sched/fair: Fix statistics with delayed dequeue To: Vincent Guittot , Luis Machado Cc: Mike Galbraith , mingo@redhat.com, peterz@infradead.org, juri.lelli@redhat.com, rostedt@goodmis.org, bsegall@google.com, mgorman@suse.de, vschneid@redhat.com, linux-kernel@vger.kernel.org, kprateek.nayak@amd.com, pauld@redhat.com References: <20241129161756.3081386-1-vincent.guittot@linaro.org> <227863d758551e75cd0807a5f1f31916d695205b.camel@gmx.de> Content-Language: en-US From: Dietmar Eggemann In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 02/12/2024 10:59, Vincent Guittot wrote: > On Mon, 2 Dec 2024 at 10:23, Luis Machado wrote: >> >> On 12/2/24 09:17, Vincent Guittot wrote: >>> On Sun, 1 Dec 2024 at 14:30, Mike Galbraith wrote: >>>> >>>> Greetings, >>>> >>>> On Fri, 2024-11-29 at 17:17 +0100, Vincent Guittot wrote: [...] >>>>> h_nr_runnable is used in several places to make decision on load balance: >>>>> - PELT runnable_avg >>>>> - deciding if a group is overloaded or has spare capacity >>>>> - numa stats >>>>> - reduced capacity management >>>>> - load balance between groups >>>> >>>> I took the series for a spin in tip v6.12-10334-gb1b238fba309, but >>>> runnable seems to have an off-by-one issue, causing it to wander ever >>>> further south. >>>> >>>> patches 1-3 applied. >>>> .h_nr_runnable : -3046 >>>> .runnable_avg : 450189777126 >>> >>> Yeah, I messed up something around finish_delayed_dequeue_entity(). >>> I'm' going to prepare a v3> >> >> Maybe something similar to what I ran into here? >> >> https://lore.kernel.org/lkml/6df12fde-1e0d-445f-8f8a-736d11f9ee41@arm.com/ > > I'm going to have a look Looks like this is not an issue anymore since commit 98442f0ccd82 ("sched: Fix delayed_dequeue vs switched_from_fair()") removed finish_delayed_dequeue_entity() from switched_from_fair() in the meantime. [...]