From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from dpdk.org (dpdk.org [92.243.14.124]) by inbox.dpdk.org (Postfix) with ESMTP id 3760BA04F0; Mon, 13 Jan 2020 17:13:33 +0100 (CET) Received: from [92.243.14.124] (localhost [127.0.0.1]) by dpdk.org (Postfix) with ESMTP id CA7621C2F1; Mon, 13 Jan 2020 17:13:32 +0100 (CET) Received: from mga05.intel.com (mga05.intel.com [192.55.52.43]) by dpdk.org (Postfix) with ESMTP id DED5B1C200; Mon, 13 Jan 2020 17:13:30 +0100 (CET) X-Amp-Result: UNKNOWN X-Amp-Original-Verdict: FILE UNKNOWN X-Amp-File-Uploaded: False Received: from orsmga003.jf.intel.com ([10.7.209.27]) by fmsmga105.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 13 Jan 2020 08:13:29 -0800 X-IronPort-AV: E=Sophos;i="5.69,429,1571727600"; d="scan'208";a="224940415" Received: from bricha3-mobl.ger.corp.intel.com ([10.237.221.26]) by orsmga003-auth.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-SHA; 13 Jan 2020 08:13:02 -0800 Date: Mon, 13 Jan 2020 16:12:59 +0000 From: Bruce Richardson To: Jerin Jacob Cc: Jerin Jacob Kollanukkaran , "dev@dpdk.org" , Thomas Monjalon , David Marchand , Ferruh Yigit , Andrew Rybchenko , Ajit Khaparde , Qi Zhang , Xiaolong Ye , Raslan Darawsheh , Maxime Coquelin , Tiwei Bie , Akhil Goyal , Luca Boccassi , Kevin Traynor , "maintainers@dpdk.org" , John McNamara , Marko Kovacevic , Ray Kinsella , Aaron Conole , Michael Santana , Harry van Haaren , Cristian Dumitrescu , Phil Yang , Joyce Kong , Mattias =?iso-8859-1?Q?R=F6nnblom?= , Jan Viktorin , Gavin Hu , David Christensen , Konstantin Ananyev , Anatoly Burakov , Harini Ramakrishnan , Omar Cardona , Anand Rawat , Olivier Matz , Gage Eads , Adrien Mazarguil , Nicolas Chautru , Declan Doherty , Fiona Trahe , Ashish Gupta , Erik Gabriel Carrillo , Abhinandan Gujjar , Hemant Agrawal , "Artem V. Andreev" , Nithin Kumar Dabilpuram , Vamsi Krishna Attunuru , Rosen Xu , Sachin Saxena , Stephen Hemminger , Chas Williams , "John W. Linville" , Prasun Kapoor , Marcin Wojtas , Michal Krawczyk , Guy Tzalik , Evgeny Schemeilin , Igor Chauskin , Ravi Kumar , Igor Russkikh , Pavel Belous , Shepard Siegel , Ed Czeck , John Miller , Somnath Kotur , Maciej Czekaj , Shijith Thotton , Srisivasubramanian Srinivasan , Rahul Lakkireddy , John Daley , Hyong Youb Kim , "Wei Hu (Xavier" , "Min Hu (Connor" , Yisen Zhuang , Ziyang Xuan , Xiaoyun Wang , Guoyang Zhou , Beilei Xing , Xiao Wang , Jingjing Wu , Wenzhuo Lu , Qiming Yang , Tomasz Duszynski , Liron Himi , Zyta Szpak , Kiran Kumar Kokkilagadda , Matan Azrad , Shahaf Shuler , Viacheslav Ovsiienko , "K. Y. Srinivasan" , Haiyang Zhang , Jan Remes , Heinrich Kuhn , Jan Gutter , Gagandeep Singh , Rasesh Mody , Shahed Shaikh , Yong Wang , Zhihong Wang , Steven Webster , Matt Peters , Keith Wiles , Tetsuya Mukawa , Jasvinder Singh , Jakub Grajciar , Ruifeng Wang , Anoob Joseph , Fan Zhang , Pablo de Lara , John Griffin , Deepak Kumar Jain , Michael Shamis , Nagadheeraj Rottela , Srikanth Jampala , Ankur Dwivedi , Jay Zhou , Lee Daly , Sunila Sahu , Nipun Gupta , Liang Ma , Peter Mccarthy , Tianfei zhang , Satha Koteswara Rao Kottidi , Xiaoyun Li , Bernard Iremonger , Vladimir Medvedkin , David Hunt , Reshma Pattan , Byron Marohn , Sameh Gobriel , Yipeng Wang , Honnappa Nagarahalli , Robert Sanford , Kevin Laatz , Maryam Tahhan , Ori Kam , Radu Nicolau , Tomasz Kantecki , Sunil Kumar Kori , Pavan Nikhilesh Bhagavatula , Kirill Rybalchenko , "Kadam, Pallavi" Message-ID: <20200113161259.GE1645@bricha3-MOBL.ger.corp.intel.com> References: <20200113130543.GC1645@bricha3-MOBL.ger.corp.intel.com> <20200113145823.GD1645@bricha3-MOBL.ger.corp.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.12.1 (2019-06-15) Subject: Re: [dpdk-dev] [RFC] DPDK Trace support X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org Sender: "dev" On Mon, Jan 13, 2020 at 08:43:01PM +0530, Jerin Jacob wrote: > On Mon, Jan 13, 2020 at 8:28 PM Bruce Richardson > wrote: > > > > On Mon, Jan 13, 2020 at 08:16:07PM +0530, Jerin Jacob wrote: > > > On Mon, Jan 13, 2020 at 6:36 PM Bruce Richardson > > > wrote: > > > > > > > > > > > > > So, Probably it good to have native CTF emitter in DPDK and reuse all > > > > > open-source trace viewer(babeltrace and TraceCompass) and format(CTF) infrastructure. > > > > > I think, it would be best of both world. > > > > > > > > > > Any thoughts on this subject? Based on the community feedback, I can work on the patch for v20.05. > > > > > > > > Forgive my ignorance of LTTng, but is there the concept of > > > > enabling/disabling the trace points? If so, the overhead you refer to, that > > > > is presumably with the trace enabled? > > > > > > Yes this is when trace is enabled. If the trace is disabled then it > > > will be the only a handful of cycles. > > > > > Two follow-on questions: > > 1. Is the trace enable/disable dynamic at runtime? > > Yes. See the requirement section. > > > 2. Have you investigated how low the "handful of cycles" actually is? > > Yes. it is around 1 to 3 cycles based on the arch. it boils down to > mostly a branch hit/miss on a memory location > embedded in a C macro. > That seems impressively low, which is great news! /Bruce