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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> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20250203084306.GC505@noisy.programming.kicks-ass.net> X-Rspam-User: X-Rspamd-Queue-Id: 0BA4140009 X-Rspamd-Server: rspam10 X-Stat-Signature: 9u16wuaaizuh9tsjxu69h8sdjnffpbn3 X-HE-Tag: 1738572835-565976 X-HE-Meta: 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 qntDzc5a NVzbB46GEKkkhnCF8Iv1QwCtpPxX8/RlR2nclRBskY4Vu+v/AGUf0Uj9sWknKPdeV2XhmWIMPhIcgSRWdudJY/i69z4J+wj4kcgykn4lrfrMxuMI7XrSIGkQoTHMakhyjgpxjKVRb6JBXnIJn/eR96F+eIIJyIeG1EWxbFh4sH0fPLShK1rybkBZOZnNs+wXQzY9ulzDg0oAL8f0lKplczitqFde/vrB5g/LSMUJw9dLm20RFRvdWrAiODcDBFhlCGOsPsgMxXmXtkyc= X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: 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 :-)