Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751183Ab2J1KM3 (ORCPT ); Sun, 28 Oct 2012 06:12:29 -0400 Received: from mail-vb0-f46.google.com ([209.85.212.46]:44318 "EHLO mail-vb0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750792Ab2J1KM1 (ORCPT ); Sun, 28 Oct 2012 06:12:27 -0400 MIME-Version: 1.0 In-Reply-To: <20120823141506.442637130@google.com> References: <20120823141422.444396696@google.com> <20120823141506.442637130@google.com> Date: Sun, 28 Oct 2012 15:42:26 +0530 Message-ID: Subject: Re: [patch 02/16] sched: maintain per-rq runnable averages From: Preeti Murthy To: pjt@google.com, Ben Segall Cc: linux-kernel@vger.kernel.org, Peter Zijlstra , Ingo Molnar , Vaidyanathan Srinivasan , Srivatsa Vaddagiri , Kamalesh Babulal , Venki Pallipadi , Mike Galbraith , Vincent Guittot , Nikunj A Dadhania , Morten Rasmussen , "Paul E. McKenney" , Namhyung Kim Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1502 Lines: 45 Hi Paul, Ben, A few queries regarding this patch: 1.What exactly is the significance of introducing sched_avg structure for a runqueue? If I have understood correctly, sched_avg keeps track of how long a task has been active, how long has it been serviced by the processor and its lifetime.How does this apply analogously to the runqueue? 2.Is this a right measure to overwrite rq->load.weight because the rq->sched_avg does not seem to take care of task priorities.IOW, what is the idea behind introducing this metric for the runqueue? Why cant the run queue load be updated the same way as the cfs_rq load is updated: cfs_rq->runnable_load_avg and cfs_rq->blocked_load_avg. 3.What is the significance of passing rq->nr_running in enqueue_task_fair while updating the run queue load? Because __update_entity_runnable_avg does not treat this argument any differently if it is >1. Thank you Regards Preeti U Murthy On Thu, Aug 23, 2012 at 7:44 PM, wrote: > From: Ben Segall > > Since runqueues do not have a corresponding sched_entity we instead embed a > sched_avg structure directly. > > Signed-off-by: Ben Segall > Reviewed-by: Paul Turner > --- -- 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/