Return-Path: linux-nfs-owner@vger.kernel.org Received: from mout.gmx.net ([212.227.15.19]:52335 "EHLO mout.gmx.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1762348Ab3JQUmT (ORCPT ); Thu, 17 Oct 2013 16:42:19 -0400 Received: from [192.168.178.60] ([84.173.47.244]) by mail.gmx.com (mrgmx102) with ESMTPSA (Nemesis) id 0La2Xx-1W130Z0HpF-00lpth for ; Thu, 17 Oct 2013 22:42:18 +0200 Message-ID: <52604BA9.20104@gmx.de> Date: Thu, 17 Oct 2013 22:42:17 +0200 From: Helge Deller MIME-Version: 1.0 To: Linux Kernel Development , NFS list , list parisc-linux Subject: 3.12-rcX - NFS regression - kswapd0 / kswapd1 stays using 100% CPU? Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-nfs-owner@vger.kernel.org List-ID: I'm seeing a regression with current kernel git head when using NFS-mounts. Architecture in my case is parisc, although I don't think that this is relevant. At least kernel 3.10 (and I think 3.11) didn't showed that problem. The symtom is, that "top" shows high usage of either kswapd0 or kswapd1. Here is an output with kswapd1: PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND 37 root 20 0 0 0 0 R 91.8 0.0 63:00.40 kswapd1 28448 root 20 0 3252 1428 1060 R 15.3 0.0 0:00.09 top 1 root 20 0 2784 988 852 S 0.0 0.0 0:09.95 init This is what ps shows: lsXXXX:~# ps -ef | grep mount root 1181 1 0 14:51 ? 00:00:18 /usr/sbin/automount --pid-file /var/run/autofs.pid root 25331 1181 0 21:25 ? 00:00:00 /bin/mount -n -t nfs -s -o nolock,rw,hard,intr homes:/unixhome1 /net/home1 root 25332 25331 0 21:25 ? 00:00:00 /sbin/mount.nfs homes:/unixhome1 /net/home1 -s -n -o rw,nolock,hard,intr And using sysrq to show the blocked tasks I get in syslog: SysRq : Show Blocked State mount.nfs D 00000000401040c0 0 25332 25331 0x00000010 Backtrace: [<0000000040113a68>] __schedule+0x500/0x810 I know it's not a problem of the NFS server, since the same mount is still ok on other machines. The NFS directory was already mounted and in use when this mount happened again (called by cron-job). Any ideas? Helge