From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755175AbYLDDwd (ORCPT ); Wed, 3 Dec 2008 22:52:33 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753106AbYLDDwX (ORCPT ); Wed, 3 Dec 2008 22:52:23 -0500 Received: from cn.fujitsu.com ([222.73.24.84]:53619 "EHLO song.cn.fujitsu.com" rhost-flags-OK-FAIL-OK-OK) by vger.kernel.org with ESMTP id S1751775AbYLDDwW (ORCPT ); Wed, 3 Dec 2008 22:52:22 -0500 Message-ID: <4937533C.3040203@cn.fujitsu.com> Date: Thu, 04 Dec 2008 11:49:16 +0800 From: Lai Jiangshan User-Agent: Thunderbird 2.0.0.18 (Windows/20081105) MIME-Version: 1.0 To: Mathieu Desnoyers CC: ltt-dev@lists.casi.polymtl.ca, Zhaolei , Ingo Molnar , Steven Rostedt , linux-kernel@vger.kernel.org Subject: Re: LTTng kernel integration roadmap, update References: <20081124112842.GA15615@Krystal> In-Reply-To: <20081124112842.GA15615@Krystal> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Mathieu Desnoyers wrote: > - Marker ID management > Background : > The markers are currently used to identify the numerical event IDs > associated with a named event as well as the event types (format > string) associated with that event. Those two informations are kept in > a table written in the metadata channel. A "channel" could be thought > as being a set of per-cpu buffers, where information transits. This > information would typically be related to a specific tracer. Note, > however, that the information generated by a tracer should always be > parseable generically and be transformable into text output by a > simple parser, because we want to permit analysis across information > logged by the various tracer. > > Action item : > The current event IDs are global to the whole kernel. It would be > beneficial to change their scope so they are per-channel instead, > because we can then encode most events in the low-order bits of the > event ID bits, therefore keeping events as small as possible. > Hi, Mathieu Desnoyers: It also required by ASCII text output. ASCII text output needs get name&fmt from eID, but In current code, I cannot find a reliable way to get name&fmt from eID. And also, in the kernel space, we must get name&fmt from eID as fast as possible by reason of performance. So I cannot use metadata channel for it. When "Add periodical subbuffer flush for streaming" and "Marker ID management" will done? Thanks, Lai.