From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757240AbcAOJtv (ORCPT ); Fri, 15 Jan 2016 04:49:51 -0500 Received: from mail-wm0-f42.google.com ([74.125.82.42]:36958 "EHLO mail-wm0-f42.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756913AbcAOJtr convert rfc822-to-8bit (ORCPT ); Fri, 15 Jan 2016 04:49:47 -0500 Date: Fri, 15 Jan 2016 10:49:37 +0100 From: Luca Abeni To: Peter Zijlstra Cc: linux-kernel@vger.kernel.org, Ingo Molnar , Juri Lelli Subject: Re: [RFC 8/8] Do not reclaim the whole CPU bandwidth Message-ID: <20160115104937.6a11cdc4@luca-1225C> In-Reply-To: <20160115085004.GE3421@worktop> References: <1452785094-3086-1-git-send-email-luca.abeni@unitn.it> <1452785094-3086-9-git-send-email-luca.abeni@unitn.it> <20160114195904.GH6357@twins.programming.kicks-ass.net> <5698ABFD.1040704@unitn.it> <20160115085004.GE3421@worktop> X-Mailer: Claws Mail 3.8.0 (GTK+ 2.24.10; i686-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, 15 Jan 2016 09:50:04 +0100 Peter Zijlstra wrote: [...] > The trouble is with interfaces. Once we expose them we're stuck with > them. And from that POV I think an explicit SCHED_OTHER server (or a > minimum budget for a slack time scheme) makes more sense. > > It provides this same information while also providing more benefit, > no? >>From an interface point of view, I agree. > > >That would maybe fit in nicely with the DL based FIFO/RR servers > > >from this other pending project. > > Yes, this reminds me about the half-finished patch for RT > > throttling using SCHED_DEADLINE... But that patch needs much more > > work IMHO. > > IIRC two years ago at RTLWS there was a presentation that the SMP > issues were 'solved' and they would be posting the patches 'soon'. Do you mean this paper? http://retis.sssup.it/~nino/publication/rtlws14bdm.pdf I started from that patch, and I have something that "basically works", but I am still discussing some theoretical and implementation issues with the paper's authors. Luca