From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261260AbVFNGzz (ORCPT ); Tue, 14 Jun 2005 02:55:55 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261268AbVFNGzz (ORCPT ); Tue, 14 Jun 2005 02:55:55 -0400 Received: from [151.38.19.110] ([151.38.19.110]:14771 "HELO develer.com") by vger.kernel.org with SMTP id S261260AbVFNGzr (ORCPT ); Tue, 14 Jun 2005 02:55:47 -0400 Message-ID: <42AE7F5C.3000209@develer.com> Date: Tue, 14 Jun 2005 08:55:24 +0200 From: Bernardo Innocenti User-Agent: Mozilla Thunderbird 1.0.2-6 (X11/20050513) X-Accept-Language: en-us, en MIME-Version: 1.0 To: linux-kernel@vger.kernel.org Subject: Audit / Netlink slowness X-Enigmail-Version: 0.91.0.0 OpenPGP: id=FC6A66CA; url=https://www.develer.com/~bernie/gpgkey.txt Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Hello, on a server running kernel 2.6.11-1.1369_FC4, both ssh and su where taking a longish amount of time (over >1.5 sec.) Running "strace -r 2>strace.out su", I discovered that netlink communication is the major cause of slowdown. "su" connects to a NETLINK_AUDIT socket 3 or 4 times. Each time it does 2 sendto() + recvfrom() operations, with a latency of ~200ms. This adds up to 800ms wasted time. Disabling CONFIG_AUDIT in the kernel makes su and ssh very fast again. Is this behavior to be expected? CONFIG_AUDIT is enabled by default in FC4, so many people are going to be hit by this problem. Please Cc me in replies as I'm not subrscribed to the lkml. -- // Bernardo Innocenti - Develer S.r.l., R&D dept. \X/ http://www.develer.com/