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bh=1YvrhE8TYy7MSDseUcEX6cz+zJ82RxWENHKzY8nEqT8=; b=ZHPJPU+D5hwpm4wgpiMkbWmAxe zXeC9sXfI+1FJnmhRYSQcLRzNzJM4biKq0RAhRlaWBiTbu7fVxyM62i/DPuAWZ/QapdcdXA13H69b 5CgUBm7Ejn1AeJZHCANVRys0942eAYLDwkZRr5j2FULQtNrk9WDqEtlduc69/83QPIV+RoriSTIRQ a11icLFVn3uMaB36w7E2w9dfiPtrOUhmWSOIVakxOe4fyvcWea1lTxsw7JbE33cJ17IV3dcXJI4ok 7embbdWMXspwSvH7rH0e7bQGxpMI4e3BHjN3f+XmScIEf0+vR5qC1i0YeHWWCM8KX8IKjNJK0o5Uu FaqJ+82g==; Received: from j130084.upc-j.chello.nl ([24.132.130.84] helo=noisy.programming.kicks-ass.net) by desiato.infradead.org with esmtpsa (Exim 4.97.1 #2 (Red Hat Linux)) id 1rvBZ6-000000091se-2gk3; Fri, 12 Apr 2024 07:43:17 +0000 Received: by noisy.programming.kicks-ass.net (Postfix, from userid 1000) id 4DD8A3004D5; Fri, 12 Apr 2024 09:43:16 +0200 (CEST) Date: Fri, 12 Apr 2024 09:43:16 +0200 From: Peter Zijlstra To: Daniel Bristot de Oliveira Cc: Ingo Molnar , Juri Lelli , Vincent Guittot , Dietmar Eggemann , Steven Rostedt , Ben Segall , Mel Gorman , Valentin Schneider , linux-kernel@vger.kernel.org, Luca Abeni , Tommaso Cucinotta , Thomas Gleixner , Joel Fernandes , Vineeth Pillai , Shuah Khan , Phil Auld , Suleiman Souhlal , Youssef Esmat Subject: Re: [PATCH V6 3/6] sched/fair: Fair server interface Message-ID: <20240412074316.GF30852@noisy.programming.kicks-ass.net> References: <1abba9e7f47ad4a5dfd8b2dfb59aa607983cdce4.1712337227.git.bristot@kernel.org> <20240411144327.GB40213@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: On Thu, Apr 11, 2024 at 05:02:41PM +0200, Daniel Bristot de Oliveira wrote: > On 4/11/24 16:43, Peter Zijlstra wrote: > > The 'defer' thing is dubious though, I don't suppose anybody would ever > > want to actually change that, other than you while poking around at this > > code, right? > > In a setup where all real-time tasks are DL (without fixed-priority tasks (FIFO/RR)) > the defer = 0 makes more sense because the bandwidth is reserved anyways, and the > DL server would have a relatively low prio (long period). Tell me more -- how is it better in that case? I would think it wouldn't matter much.