From mboxrd@z Thu Jan 1 00:00:00 1970 From: Carsten Emde Subject: Re: cpu stall and hyperthread Date: Fri, 06 Jul 2012 00:48:53 +0200 Message-ID: <4FF619D5.3090206@osadl.org> References: <4FEBCDDE.60503@gmail.com> <4FF351C6.3000100@gmail.com> <4FF4C94A.6040105@osadl.org> <4FF5DFDC.9010501@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: linux-rt-users@vger.kernel.org To: Dong Liu Return-path: Received: from toro.web-alm.net ([62.245.132.31]:40963 "EHLO toro.web-alm.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932163Ab2GEWwI (ORCPT ); Thu, 5 Jul 2012 18:52:08 -0400 In-Reply-To: <4FF5DFDC.9010501@gmail.com> Sender: linux-rt-users-owner@vger.kernel.org List-ID: Hi Dong, > I tried to disable CONFIG_RT_GROUP_SCHED, but I still got cpu stalls! Hmm, sorry. I hoped it would work. > Is there a recommended config for the RT patch? Not really. In the x86 distro case, we base everything on the distro configuration, e.g. using cp /boot/config-`uname -r` .config We then disable CONFIG_RT_GROUP_SCHED and CONFIG_DEBUG_STACKOVERFLOW, because they are known to cause trouble and long latencies, respectively. In addition, we enable diagnostics such a latency histograms. That's all. An alternative approach would be to select a QA farm system that is close to your hardware and distro and use the same settings on your system. A list of all farm systems sorted by distro is here -> https://www.osadl.org/?id=1070; clicking on the system name in the first row of this table will display its entire profile. This includes kernel parameter, hardware data and, of course, the kernel configuration. Sometimes, there is also a quilt series, in case we temporarily use off-tree patches that are on their way to mainline. Would be interesting to see whether your system also stalls when a configuration is used that is successful here. -Carsten.