From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-la0-f44.google.com (mail-la0-f44.google.com [209.85.215.44]) by kanga.kvack.org (Postfix) with ESMTP id F35E4900021 for ; Mon, 27 Oct 2014 18:01:44 -0400 (EDT) Received: by mail-la0-f44.google.com with SMTP id gf13so380239lab.31 for ; Mon, 27 Oct 2014 15:01:44 -0700 (PDT) Received: from mx2.suse.de (cantor2.suse.de. [195.135.220.15]) by mx.google.com with ESMTPS id g7si22011422lbs.0.2014.10.27.15.01.42 for (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Mon, 27 Oct 2014 15:01:43 -0700 (PDT) Message-ID: <544EC0C5.7050808@suse.cz> Date: Mon, 27 Oct 2014 23:01:41 +0100 From: Vlastimil Babka MIME-Version: 1.0 Subject: Re: isolate_freepages_block(): very high intermittent overhead References: <20141027204003.GB348@x4> In-Reply-To: <20141027204003.GB348@x4> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Markus Trippelsdorf , linux-mm@kvack.org On 10/27/2014 09:40 PM, Markus Trippelsdorf wrote: > On my v3.18-rc2 kernel isolate_freepages_block() sometimes shows up very > high (>20%) in perf top during the configuration phase of software > builds. It increases build time considerably. > > Unfortunately the issue is not 100% reproducible, because it appears > only intermittently. And the symptoms vanish after a few minutes. Does it happen for long enough so you can capture it by perf record -g ? Vlastimil > I think the "mm, compaction" series from Vlastimil is to blame, but it's > hard to be sure when bisection doesn't work. > -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org