Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753822AbYHKOzw (ORCPT ); Mon, 11 Aug 2008 10:55:52 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751005AbYHKOzp (ORCPT ); Mon, 11 Aug 2008 10:55:45 -0400 Received: from hrndva-omtalb.mail.rr.com ([71.74.56.123]:52994 "EHLO hrndva-omtalb.mail.rr.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750989AbYHKOzo (ORCPT ); Mon, 11 Aug 2008 10:55:44 -0400 Date: Mon, 11 Aug 2008 10:55:42 -0400 (EDT) From: Steven Rostedt X-X-Sender: rostedt@gandalf.stny.rr.com To: Andi Kleen cc: Valdis.Kletnieks@vt.edu, Peter Zijlstra , Ingo Molnar , Andrew Morton , torvalds@linux-foundation.org, tglx@linutronix.de, marcin.slusarz@gmail.com, linux-kernel@vger.kernel.org, davem@davemloft.net, paulmck@linux.vnet.ibm.com Subject: Re: [PATCH] printk: robustify printk In-Reply-To: <20080811142900.GU9038@one.firstfloor.org> Message-ID: References: <1218219269.29098.5.camel@lappy.programming.kicks-ass.net> <20080808121428.646a8b3c.akpm@linux-foundation.org> <1218223269.29098.12.camel@lappy.programming.kicks-ass.net> <1218224829.29098.19.camel@lappy.programming.kicks-ass.net> <20080811104526.GA15186@elte.hu> <87zlnj24qc.fsf@basil.nowhere.org> <1218453726.10800.63.camel@twins> <20080811114243.GO9038@one.firstfloor.org> <22551.1218464121@turing-police.cc.vt.edu> <20080811142900.GU9038@one.firstfloor.org> User-Agent: Alpine 1.10 (DEB 962 2008-03-14) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1090 Lines: 28 On Mon, 11 Aug 2008, Andi Kleen wrote: > $INSERT-ANY-OTHER-PRINTK-USE$ > > The point was that printk may have been perfectly adequate for > them with its existing buffer sizes and dynamic wake up frequency, > and might not anymore with the timer wakeup change. Essentially > it is making a widely used kernel facility more fragile. I've measured several latencies in the kernel that would cause klogd to take serveral jiffies to wake up. I highly doubt that adding one jiffy will break anything. And if it did, then it would show a bug in their system. If adding one jiffy causes lost data, then the system administrators are relying on a utility (klogd) that can easily fail them without these patches. If we are making a highly fragile setup a bit more fragile, maybe it will wake the IT guys up to change their setup. -- Steve -- 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/