From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754507Ab1A1BsG (ORCPT ); Thu, 27 Jan 2011 20:48:06 -0500 Received: from wolverine01.qualcomm.com ([199.106.114.254]:6057 "EHLO wolverine01.qualcomm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753863Ab1A1BsB (ORCPT ); Thu, 27 Jan 2011 20:48:01 -0500 X-IronPort-AV: E=McAfee;i="5400,1158,6239"; a="72275229" Message-ID: <4D422051.4090407@codeaurora.org> Date: Thu, 27 Jan 2011 17:48:01 -0800 From: Michael Bohan User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.9.2.13) Gecko/20101207 Thunderbird/3.1.7 MIME-Version: 1.0 To: Paul Menage CC: Bryan Huntsman , Colin Cross , Li Zefan , containers@lists.linux-foundation.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 1/2] cgroup: Set CGRP_RELEASABLE when adding to a cgroup References: <1290577024-12347-1-git-send-email-ccross@android.com> <4D42192C.9000701@codeaurora.org> In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 1/27/2011 5:30 PM, Paul Menage wrote: > On Thu, Jan 27, 2011 at 5:17 PM, Bryan Huntsman wrote: >> >> Tested-by: Mike Bohan >> >> I'm responding on Mike's behalf and adding him to this thread. This >> patch improves launch time of a test app from ~700ms to ~250ms on MSM, >> with much lower variance across tests. We also see UI latency >> improvements, but have not quantified the gains. >> > > Is this attached to the wrong patch? I'd thought that it was the other > patch (removing the rcu_synchronize()) that's the performance booster. > This one is more about preserving the semantics of the notification > API. You are correct. "[PATCH 2/2] cgroup: Remove call to synchronize_rcu in cgroup_attach_task" improved the performance. To be more correct, I tested this patch (eg. "cgroup: Set CGRP_RELEASABLE when adding to a cgroup") to the degree that it didn't appear to cause any stability or functional regressions when performing the simple benchmark procedure described above. I did also test "[PATCH 2/2] cgroup: Remove call to synchronize_rcu in cgroup_attach_task" independently of this patch to verify that it alone improved the performance. Thanks, Mike -- Employee of Qualcomm Innovation Center, Inc. Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum