From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932145Ab0CDRPr (ORCPT ); Thu, 4 Mar 2010 12:15:47 -0500 Received: from fallback.mail.elte.hu ([157.181.151.13]:49270 "EHLO fallback.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756723Ab0CDRPp convert rfc822-to-8bit (ORCPT ); Thu, 4 Mar 2010 12:15:45 -0500 Date: Thu, 4 Mar 2010 12:18:56 +0100 From: Ingo Molnar To: Tom Zanussi Cc: linux-kernel@vger.kernel.org, fweisbec@gmail.com, rostedt@goodmis.org, k-keiichi@bx.jp.nec.com Subject: Re: [RFC PATCH 0/7] perf: 'live mode' Message-ID: <20100304111856.GE21977@elte.hu> References: <1267599929-8310-1-git-send-email-tzanussi@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: 8BIT In-Reply-To: <1267599929-8310-1-git-send-email-tzanussi@gmail.com> User-Agent: Mutt/1.5.20 (2009-08-17) X-ELTE-SpamScore: 0.0 X-ELTE-SpamLevel: X-ELTE-SpamCheck: no X-ELTE-SpamVersion: ELTE 2.0 X-ELTE-SpamCheck-Details: score=0.0 required=5.9 tests=none autolearn=no SpamAssassin version=3.2.5 _SUMMARY_ Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org * Tom Zanussi wrote: > Currently, a perf session entails two steps: first 'perf record' or 'perf > trace record' records the perf data to disk, then 'perf report' or 'perf > trace report' reads the saved data from disk and reports the results. > > This experimental patchset makes some changes to perf that instead allow the > perf data to be piped directly from the record step to the report step, > without ever touching the disk. Very nice! > Obviously, it would be better to have a real top-like display for these > rather than a continuously scrolling mode like this, and of course it will > be much more useful once we get the syscall name injection events going (the > column on the left shows syscall numbers only). It's still useful for ad-hoc tracing! Side-note, it might make sense to expose the 'clear' escape sequence somehow in an easy fashion:  to make it non-scrolling ;-) via a pre-provided method. > There are some rough edges and inefficiencies, and I guess 'event injection' > may be a better way to do this in the end, but it seems to work pretty well > already, and I think it shows how useful such a capability can be. I'm all for it. Frederic, Steve, what do you think? Ingo