From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756829Ab0CaT1J (ORCPT ); Wed, 31 Mar 2010 15:27:09 -0400 Received: from tx2ehsobe002.messaging.microsoft.com ([65.55.88.12]:27384 "EHLO TX2EHSOBE004.bigfish.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754905Ab0CaT1H (ORCPT ); Wed, 31 Mar 2010 15:27:07 -0400 X-SpamScore: -34 X-BigFish: VPS-34(zz1432R98dN936eM9371Pzz1202hz4fhz2ba5Mz2fh2a8h6bh61h) X-Spam-TCS-SCL: 0:0 X-FB-SS: 5, Message-ID: <4BB3A1F5.1050902@am.sony.com> Date: Wed, 31 Mar 2010 12:26:45 -0700 From: Tim Bird User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.1.8) Gecko/20100301 Fedora/3.0.3-1.fc12 Thunderbird/3.0.3 MIME-Version: 1.0 To: "swb6@aber.ac.uk" CC: "linux-kernel@vger.kernel.org" Subject: Re: Ftrace and Systemtap References: <40fe3da502608d32ff82523c57a62da1.squirrel@webmail.aber.ac.uk> In-Reply-To: <40fe3da502608d32ff82523c57a62da1.squirrel@webmail.aber.ac.uk> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit X-Reverse-DNS: mail7.fw-bc.sony.com Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 03/31/2010 10:36 AM, swb6@aber.ac.uk wrote: > Hi, > I am currently writing up my > dissertation based on dynamic tracing and reducing the learning curve to > understanding the UNIX kernel. I used two dynamic tracing technologies > (Systemtap and Dtrace) to monitor some virtual machines on a network. > Whilst going over my initial review of technologies in the area of dynamic > tracing I realised I had underestimated ftrace, and even dismissed it as > not being dynamic. However I read hear (http://lwn.net/Articles/343766/) > that you were as of July last year trying to introduce a patch that would > allow ftrace the ability to dynamically trace. Also it would be completely > instrumented from the command line without the need to compile a kernel > module al la Systemtap. > > My question is do you think Systemtap will be replaced by ftrace in the > future if so I feel I may need to include this fact in my updated > technology review. Systemtap addresses a different set of needs than ftrace. Ftrace has been dynamic for some time, but in a different way than Systemtap. I don't see either system going away soon. ============================= Tim Bird Architecture Group Chair, CE Linux Forum Senior Staff Engineer, Sony Corporation of America =============================