Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932282AbWIOV2Z (ORCPT ); Fri, 15 Sep 2006 17:28:25 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932281AbWIOV2Z (ORCPT ); Fri, 15 Sep 2006 17:28:25 -0400 Received: from scrub.xs4all.nl ([194.109.195.176]:57256 "EHLO scrub.xs4all.nl") by vger.kernel.org with ESMTP id S932282AbWIOV2Y (ORCPT ); Fri, 15 Sep 2006 17:28:24 -0400 Date: Fri, 15 Sep 2006 23:27:58 +0200 (CEST) From: Roman Zippel X-X-Sender: roman@scrub.home To: Ingo Molnar cc: Thomas Gleixner , karim@opersys.com, Andrew Morton , Paul Mundt , Jes Sorensen , Mathieu Desnoyers , linux-kernel@vger.kernel.org, Christoph Hellwig , Ingo Molnar , Greg Kroah-Hartman , Tom Zanussi , ltt-dev@shafik.org, Michel Dagenais Subject: Re: [PATCH 0/11] LTTng-core (basic tracing infrastructure) 0.5.108 In-Reply-To: <20060915204812.GA6909@elte.hu> Message-ID: References: <450AB506.30802@sgi.com> <450AB957.2050206@opersys.com> <20060915142836.GA9288@localhost.usen.ad.jp> <450ABE08.2060107@opersys.com> <1158332447.5724.423.camel@localhost.localdomain> <20060915111644.c857b2cf.akpm@osdl.org> <1158348954.5724.481.camel@localhost.localdomain> <450B0585.5070700@opersys.com> <1158351780.5724.507.camel@localhost.localdomain> <20060915204812.GA6909@elte.hu> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2864 Lines: 67 Hi, On Fri, 15 Sep 2006, Ingo Molnar wrote: > > Nobody is taking dynamic tracing away! > > You make it sound that tracing is only possible via dynamic traces. > > If I want to use static tracepoints, why shouldn't I? > > because: > > - static tracepoints, once added, are very hard to remove - up until > eternity. (On the other hand, markers for dynamic tracers are easily > removed, either via making the dynamic tracer smarter, or by > detaching the marker via the patch(1) method. In any case, if a > marker goes away then hell does not break loose in dynamic tracing > land - but it does in static tracing land. This is simply not true, at the source level you can remove a static tracepoint as easily as a dynamic tracepoint, the effect of the missing trace information is the same either way. > - the markers needed for dynamic tracing are different from the LTT > static tracepoints. What makes the requirements so different? I would actually think it depends on the user independent of the tracing is done. > - a marker for dynamic tracing has lower performance impact than a > static tracepoint, on systems that are not being traced. (but which > have the tracing infrastructure enabled otherwise) Anyone using static tracing intents to use, which makes this point moot. > - having static tracepoints dillutes the incentive for architectures to > implement proper kprobes support. Considering the level of work needed to support efficient dynamic tracing it only withholds archs from tracing support for no good reason. > > > > there are separate project teams is because managers in key > > > > positions made the decision that they'd rather break from existing > > > > projects which had had little success mainlining and instead use > > > > their corporate bodyweight to pressure/seduce kernel developers > > > > working for them into pushing their new great which-aboslutely- > > > > has-nothing-to-do-with-this-ltt-crap-(no,no, we actually agree > > > > with you kernel developers that this is crap, this is why we're > > > > developing this new amazing thing). That's the truth plain and > > > > simple. > > > > > > Stop whining! > > > > So we're back to personal attacks now. :-( > > hm, so you dont consider the above paragraph a whine. How would you > characterize it then? A measured, balanced, on-topic technical comment? > I'm truly curious. It's sarcastic, but considering the disrespect towards Karim, I don't blame him. At some point the "whining" argument was funny, but lately it's only used to descredit people. bye, Roman - 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/