Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751218AbWIOLTA (ORCPT ); Fri, 15 Sep 2006 07:19:00 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751259AbWIOLTA (ORCPT ); Fri, 15 Sep 2006 07:19:00 -0400 Received: from outpipe-village-512-1.bc.nu ([81.2.110.250]:53151 "EHLO lxorguk.ukuu.org.uk") by vger.kernel.org with ESMTP id S1751218AbWIOLTA (ORCPT ); Fri, 15 Sep 2006 07:19:00 -0400 Subject: Re: [PATCH 0/11] LTTng-core (basic tracing infrastructure) 0.5.108 From: Alan Cox To: Tim Bird Cc: Ingo Molnar , Roman Zippel , Mathieu Desnoyers , linux-kernel@vger.kernel.org, Christoph Hellwig , Andrew Morton , Ingo Molnar , Greg Kroah-Hartman , Thomas Gleixner , Tom Zanussi , ltt-dev@shafik.org, Michel Dagenais In-Reply-To: <4509B03A.3070504@am.sony.com> References: <20060914033826.GA2194@Krystal> <20060914112718.GA7065@elte.hu> <20060914135548.GA24393@elte.hu> <20060914171320.GB1105@elte.hu> <20060914181557.GA22469@elte.hu> <4509B03A.3070504@am.sony.com> Content-Type: text/plain Content-Transfer-Encoding: 7bit Date: Fri, 15 Sep 2006 12:40:06 +0100 Message-Id: <1158320406.29932.16.camel@localhost.localdomain> Mime-Version: 1.0 X-Mailer: Evolution 2.6.2 (2.6.2-1.fc5.5) Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 884 Lines: 19 Ar Iau, 2006-09-14 am 12:40 -0700, ysgrifennodd Tim Bird: > It's only zero maintenance overhead for you. Someone has to > maintain it. The party line for years has been that in-tree > maintenance is easier than out-of-tree maintenance. That misses the entire point. If you have dynamic tracepoints you don't have any static tracepoints to maintain because you don't need them. They may be a clock or three slower but you are then going to branch into the trace tool code paths, take tlb misses, take cache misses, and eventually get back, so the cost of it being dynamic is so close to zero in the biger picture it doesn't matter. Alan - 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/