From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sven-Thorsten Dietrich Subject: Re: 2.6.35 RT support roadmap Date: Thu, 12 Aug 2010 23:05:36 -0700 Message-ID: <1281679536.7356.8.camel@baracus> References: <1281638311.7093.4.camel@marge.simson.net> <4C645567.2080308@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Cc: Mike Galbraith , Xianghua Xiao , "Walzer, Frank" , "linux-rt-users@vger.kernel.org" To: jordan johnston Return-path: Received: from mail-yw0-f46.google.com ([209.85.213.46]:39564 "EHLO mail-yw0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751640Ab0HMGFl (ORCPT ); Fri, 13 Aug 2010 02:05:41 -0400 Received: by ywh1 with SMTP id 1so755392ywh.19 for ; Thu, 12 Aug 2010 23:05:40 -0700 (PDT) In-Reply-To: Sender: linux-rt-users-owner@vger.kernel.org List-ID: On Thu, 2010-08-12 at 23:17 -0400, jordan johnston wrote: > > Google did Android and even Palm woke up (just long enough to watch its own > > demise). > > > > The rest is history. > > > > Except of course putting the RT Kernel in Android. > > As i understand it, many Android users are using the BFS patchset, and > have been for a while. BFS pretty much does what "the end result of > using the rt-patches" accomplish, minus rtirq, spin-locks, etc. You > will get the desired > responsiveness that using RT would give you. > I assume that it might well depend to some extent on whether I am pumping market data feeds into a processing model using 512 CPUs or playing a game on my Nexus-1, but I won't disagree agree with you on the importance of task-appropriate efficient scheduling, appropriate workload partitioning, and all that jazz. > Im pretty sure that is why Zen-kernel has a git repository "very > specifically" for android (BFS is the default kernel setting). I'm > sure there are other goodies for android in there too. > > www.zen-kernel.org > > I don't know much about the Android repo's state (as it's fairly new). > but worth a > look for your "rt-usage" (ie. performance/responsiveness) for android. > As i do not own an Android, i have not tested it, but i have talked > with people who do.. > > I'm waiting to see what 2.6.35 holds for RT.... but personally i am > using BFS and 2.6.34 with a lot of performance tuning (a good deal of > time spent analyzing/tuning) and i am yielding better results not > using the upstream rt-patches. > we will see what happens in 2.6.35/36.... > Sounds good. I know there has been some extensive discussion about the interpretation and applicability of the various scheduler performance metrics, including special examination of BFS vs. CFS - and I definitely think that has been hashed out in gore and detail already. But if you have some pretty plots that characterize performance for your platform, vs. Preempt-RT, I am always interested in looking at pictures and numbers about what's happening on the other side of the fence. Cheers, Sven > just my 2 cents :) > > cheers > > jordan