From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from casper.infradead.org (casper.infradead.org [90.155.50.34]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id A96B95336E; Mon, 3 Feb 2025 08:54:02 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=90.155.50.34 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1738572844; cv=none; b=AHB6qgGB6ksuICXN3D62oesAuh1ZgMoz0hSyvwB0/aCNYUtbQ8gAx9q6l1v5keQcqvUrNJ0y3uxD390NbyUk2B6I/oqkU9bLUJtxDLZeBtVP4uNB1qYHru5L4BtYc8ZjmG0u0joDr9gM+1G2/SxiYPVx7ZOB7iwSTQQgqwEFC2I= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1738572844; c=relaxed/simple; bh=NIx5C9OL/COcxC4emvv1A3zU1bJS2JXGwSDfdqiGEEQ=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=gwHsp8j5dtrhvjptrbD9CJwqD6KGrQy/kjrHFMHNdXc4Q0p2HJSkyljP0sn4Rc01O1pb1QfrHZk2dKCuJBpVZkNBVA+uKtxb9960/tm63CMN7DyYrG+Xono4AroPZszFSHqmVyRoopPrxlpivK7B7fIYg2V9exPuOc7i/GY4Dl4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org; spf=none smtp.mailfrom=infradead.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b=dsdFJX7y; arc=none smtp.client-ip=90.155.50.34 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=infradead.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="dsdFJX7y" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=NIx5C9OL/COcxC4emvv1A3zU1bJS2JXGwSDfdqiGEEQ=; b=dsdFJX7yJY/6M+7mcI96AZhrmD r7hiTwdtY6Q8Lf9sortAXjcdjMKF4t2JhsS87MaO5IX93TNABXnGXPkZb4kRufcfmtmsvDt8ygAVw 0DU+GAk2v/75Wbo13VLxsaOyniKlBO8hl9Cf4QriyNwbtZraw6/3Cn44KYhg0qzdbPErYDnKie5tq sgKgWRgefS/NpAgy4SlblIKnP7Il5gFKY1hJpdaJJDgtjYVJ9EDrSoYjIHyBxJv6hNFubuhhm+QS3 Z2LjXDS3/EGfO8SVOuDIIJaWB8CmDfWk5VYFrfnEehoZJypeWpqeNrbgjs2COs36yJnHYkx6YtUK0 CKy8A7Gw==; Received: from 77-249-17-89.cable.dynamic.v4.ziggo.nl ([77.249.17.89] helo=noisy.programming.kicks-ass.net) by casper.infradead.org with esmtpsa (Exim 4.98 #2 (Red Hat Linux)) id 1tesDE-00000000kwL-1R3q; Mon, 03 Feb 2025 08:53:48 +0000 Received: by noisy.programming.kicks-ass.net (Postfix, from userid 1000) id C1222300310; Mon, 3 Feb 2025 09:53:47 +0100 (CET) Date: Mon, 3 Feb 2025 09:53:47 +0100 From: Peter Zijlstra To: Steven Rostedt Cc: linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org, Thomas Gleixner , Ankur Arora , Linus Torvalds , linux-mm@kvack.org, x86@kernel.org, akpm@linux-foundation.org, luto@kernel.org, bp@alien8.de, dave.hansen@linux.intel.com, hpa@zytor.com, juri.lelli@redhat.com, vincent.guittot@linaro.org, willy@infradead.org, mgorman@suse.de, jon.grimm@amd.com, bharata@amd.com, raghavendra.kt@amd.com, boris.ostrovsky@oracle.com, konrad.wilk@oracle.com, jgross@suse.com, andrew.cooper3@citrix.com, Joel Fernandes , Vineeth Pillai , Suleiman Souhlal , Ingo Molnar , Mathieu Desnoyers , Clark Williams , bigeasy@linutronix.de, daniel.wagner@suse.com, joseph.salisbury@oracle.com, broonie@gmail.com Subject: Re: [RFC][PATCH 1/2] sched: Extended scheduler time slice Message-ID: <20250203085347.GL8385@noisy.programming.kicks-ass.net> References: <20250131225837.972218232@goodmis.org> <20250131225942.365475324@goodmis.org> <20250201115906.GB8256@noisy.programming.kicks-ass.net> <20250201181129.GA34937@noisy.programming.kicks-ass.net> <20250201180617.491ce087@batman.local.home> <20250203084306.GC505@noisy.programming.kicks-ass.net> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20250203084306.GC505@noisy.programming.kicks-ass.net> On Mon, Feb 03, 2025 at 09:43:06AM +0100, Peter Zijlstra wrote: > Lazy is not the default, nor even the recommended preemption method at > this time. Just to clarify this for people reading along; lazy is there for people to identify performance 'issues' vs voluntary such that those can be addressed. I'm not at all sure who is spending time on it, but it will probably take a while. Once it has been determined lazy is good enough -- as indicated by the distros having picked it as a default, we can look at deprecating and removing voluntary (and eventually none). Also, RT likes it :-)