From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932336AbWAUUrb (ORCPT ); Sat, 21 Jan 2006 15:47:31 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932343AbWAUUrb (ORCPT ); Sat, 21 Jan 2006 15:47:31 -0500 Received: from smtp.osdl.org ([65.172.181.4]:51600 "EHLO smtp.osdl.org") by vger.kernel.org with ESMTP id S932336AbWAUUra (ORCPT ); Sat, 21 Jan 2006 15:47:30 -0500 Date: Sat, 21 Jan 2006 12:47:09 -0800 From: Andrew Morton To: Knut Petersen Cc: linux-kernel@vger.kernel.org, torvalds@osdl.org Subject: Re: [BUG] Timer subsystem broken for Pentium M / early XEON / P6 family Message-Id: <20060121124709.28756a2d.akpm@osdl.org> In-Reply-To: <43D22139.2000208@t-online.de> References: <43D22139.2000208@t-online.de> X-Mailer: Sylpheed version 1.0.4 (GTK+ 1.2.10; i386-redhat-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Knut Petersen wrote: > > Obviously printk time jumps. But it is also inaccurate compared against > system time: 10:33:18 is > 1116 seconds after 10:14:42, and so the printk time at 10:33:18 should > be 1260+1116==2376 and not 2362. > That means printk time lost 14 seconds against system time in less that > 20 Minutes. printk-time is really just a debugging/development thing - it doesn't try to be serious. We _could_ use some more accurate time function for this, but most of them take locks, and taking locks inside printk isn't a great idea. Plus syslogd already adds timestamps.