Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752267AbaG3K5N (ORCPT ); Wed, 30 Jul 2014 06:57:13 -0400 Received: from fw-tnat.austin.arm.com ([217.140.110.23]:47961 "EHLO collaborate-mta1.arm.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751223AbaG3K5M (ORCPT ); Wed, 30 Jul 2014 06:57:12 -0400 Date: Wed, 30 Jul 2014 11:57:07 +0100 From: Morten Rasmussen To: Peter Zijlstra Cc: Yuyang Du , "mingo@redhat.com" , "linux-kernel@vger.kernel.org" , "pjt@google.com" , "bsegall@google.com" , "arjan.van.de.ven@intel.com" , "len.brown@intel.com" , "rafael.j.wysocki@intel.com" , "alan.cox@intel.com" , "mark.gross@intel.com" , "fengguang.wu@intel.com" Subject: Re: [PATCH 0/2 v4] sched: Rewrite per entity runnable load average tracking Message-ID: <20140730105707.GC3001@e103034-lin> References: <1405639567-21445-1-git-send-email-yuyang.du@intel.com> <20140718153931.GJ8700@e103034-lin> <20140727190237.GB22986@intel.com> <20140730101331.GB15761@e103687> <20140730102128.GJ19379@twins.programming.kicks-ass.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20140730102128.GJ19379@twins.programming.kicks-ass.net> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Jul 30, 2014 at 11:21:28AM +0100, Peter Zijlstra wrote: > On Wed, Jul 30, 2014 at 11:13:31AM +0100, Morten Rasmussen wrote: > > It is a very real problem when user-space uses priorities extensively > > like Android does. Tasks related to audio run at very high priorities > > but only for a very short amount of time, but due the to priority > > scaling their load ends up being several times higher than tasks running > > all the time at normal priority. Hence task load is a very poor > > indicator of utilization. > > FWIW Android (which I think does this through binder) is utterly insane > in this regard. But yes, we have to live with it. I agree that its use of priorities seems a bit extreme. I'm not trying to defend it in any way :-) -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/