Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751964AbYLOL65 (ORCPT ); Mon, 15 Dec 2008 06:58:57 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751095AbYLOL6t (ORCPT ); Mon, 15 Dec 2008 06:58:49 -0500 Received: from dovecot.org ([82.118.211.50]:52405 "EHLO dovecot.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751029AbYLOL6s (ORCPT ); Mon, 15 Dec 2008 06:58:48 -0500 X-Greylist: delayed 1629 seconds by postgrey-1.27 at vger.kernel.org; Mon, 15 Dec 2008 06:58:48 EST Message-Id: From: Timo Sirainen To: linux-kernel@vger.kernel.org Content-Type: multipart/signed; protocol="application/pgp-signature"; micalg=pgp-sha1; boundary="Apple-Mail-60--222096787" Content-Transfer-Encoding: 7bit Mime-Version: 1.0 (Apple Message framework v929.2) Subject: 2.6.27 inotify causes unkillable processes with 100% CPU usage Date: Mon, 15 Dec 2008 13:31:29 +0200 Cc: nuitari-dovecot@nuitari.net, Arno Wald , David Rosenstrauch X-Pgp-Agent: GPGMail d51 (Leopard) X-Mailer: Apple Mail (2.929.2) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2176 Lines: 58 This is an OpenPGP/MIME signed message (RFC 2440 and 3156) --Apple-Mail-60--222096787 Content-Type: text/plain; charset=US-ASCII; format=flowed; delsp=yes Content-Transfer-Encoding: 7bit There appears to be a bug in 2.6.27 and inotify where it causes processes in running state to eat 100% CPU and they can't be killed with kill -9, requiring a reboot to get rid of them. 3 people (Cc'd) so far have reported this to me, all of them last week. The problem shows up when running my Dovecot IMAP server. Its imap processes start hanging, apparently it can happen after running for only a couple of minutes: PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND 6717 arno 20 0 2964 1608 1192 R 100 0.2 1158:05 imap Only the imap processes hang (Dovecot has a few others). The only thing special about it is that it uses inotify. After disabling Dovecot's inotify support at least one of the people (Arno) reported that he can't reprocuce the bug anymore. He also couldn't reproduce the bug with 2.6.26 kernel. I don't think Dovecot does anything special with its inotify code. It just listens on two directories. You can find the code here: http://hg.dovecot.org/dovecot-1.1/file/f9a000ee400d/src/lib/ioloop-notify-inotify.c Kernels causing the hang: 2.6.27-9.slh.1-sidux-686 Arch Linux, kernel 2.6.27.8 Gentoo with 2.6.27-gentoo-r5, amd64, 2 dual core opterons Not causing the hang: 2.6.26-6.slh.1-sidux-686 --Apple-Mail-60--222096787 content-type: application/pgp-signature; x-mac-type=70674453; name=PGP.sig content-description: This is a digitally signed message part content-disposition: inline; filename=PGP.sig content-transfer-encoding: 7bit -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.8 (Darwin) iEYEARECAAYFAklGQBEACgkQyUhSUUBVislAQwCdELIvIxggRRFjSLVHxR1nN/MU 0TwAoJHq9DTELgo2Gyb/Y0VXZG800FW1 =CjPd -----END PGP SIGNATURE----- --Apple-Mail-60--222096787-- -- 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/