Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754379AbbGPAec (ORCPT ); Wed, 15 Jul 2015 20:34:32 -0400 Received: from know-smtprelay-omc-7.server.virginmedia.net ([80.0.253.71]:57880 "EHLO know-smtprelay-omc-7.server.virginmedia.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753248AbbGPAeb (ORCPT ); Wed, 15 Jul 2015 20:34:31 -0400 X-Originating-IP: [81.106.150.188] X-Spam: 0 X-Authority: v=2.1 cv=JuUM15MC c=1 sm=1 tr=0 a=DGj713NdaxKrsjjgQne7PA==:117 a=DGj713NdaxKrsjjgQne7PA==:17 a=NLZqzBF-AAAA:8 a=yEdEr6MRgwAA:10 a=IkcTkHD0fZMA:10 a=zOBTXjUuO1YA:10 a=l8cxvBCPkWPPBafYFdQA:9 a=QEXdDO2ut3YA:10 Date: Thu, 16 Jul 2015 01:34:19 +0100 From: Ken Moffat To: Andy Lutomirski Cc: linux-kernel@vger.kernel.org, Jeff Epler , =?iso-8859-1?Q?Fr=E9d=E9ric?= Weisbecker , Rik van Riel Subject: Re: CONFIG_NO_HZ_FULL restricts cpu usage to the equivalent of one in 4.2 Message-ID: <20150716003419.GB15221@milliways> References: <20150715162713.GA29360@milliways> <55A6AEE1.4080109@amacapital.net> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline X-Clacks-Overhead: GNU Terry Pratchett Content-Transfer-Encoding: 8bit In-Reply-To: <55A6AEE1.4080109@amacapital.net> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 776 Lines: 21 On Wed, Jul 15, 2015 at 12:05:05PM -0700, Andy Lutomirski wrote: > > Before going nuts bisecting, it could be worth running perf record -a -g -e > cycles (or perhaps -e task-clock instead of -e cycles). It could also be > worth manually sampling /proc/PID/stack a few times for a process that isn't > making as much progress as it should. > > --Andy I think Frederic has already spotted the problem - in the early bisects, everything was building on CPU 0. But thanks for the suggestion. ĸen -- This one goes up to eleven! -- 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/