From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mikael Pettersson Subject: [3.13 regression] kswapd0 and ksoftirqd/0 CPU hogs Date: Fri, 6 Jun 2014 13:38:33 +0200 Message-ID: <21393.43065.207399.530921@gargle.gargle.HOWL> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Return-path: Received: from mail-la0-f46.google.com ([209.85.215.46]:37564 "EHLO mail-la0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750740AbaFFLih (ORCPT ); Fri, 6 Jun 2014 07:38:37 -0400 Received: by mail-la0-f46.google.com with SMTP id hz20so1265720lab.5 for ; Fri, 06 Jun 2014 04:38:36 -0700 (PDT) Received: from cascade (h109n3-u-a31.ias.bredband.telia.com. [213.65.120.109]) by mx.google.com with ESMTPSA id bj7sm8702605lbc.22.2014.06.06.04.38.34 for (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Fri, 06 Jun 2014 04:38:35 -0700 (PDT) Sender: linux-m68k-owner@vger.kernel.org List-Id: linux-m68k@vger.kernel.org To: linux-m68k@vger.kernel.org Since updating my ARAnym VMs from 3.12.16 to 3.13.11 I see kswapd0 and ksoftirqd/0 consume inordinate amounts of CPU. kswapd0 often rises to about 30-50% CPU even though RAM shouldn't be anywhere near depleted (768GB, a gcc bootstrap running in a screen session). kswapd0 tends to stay this way until I drop caches, but doing that doesn't always fix it. I also sometimes see ksoftirqd/0 consume 5-30% CPU. Reverting to 3.12.16 completely eliminates these problems. I haven't tested 3.14 or 3.15-rc yet. /Mikael