Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1761478AbXLMKa1 (ORCPT ); Thu, 13 Dec 2007 05:30:27 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755984AbXLMKaP (ORCPT ); Thu, 13 Dec 2007 05:30:15 -0500 Received: from mx3.mail.elte.hu ([157.181.1.138]:48961 "EHLO mx3.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755753AbXLMKaN (ORCPT ); Thu, 13 Dec 2007 05:30:13 -0500 Date: Thu, 13 Dec 2007 11:29:39 +0100 From: Ingo Molnar To: "Metzger, Markus T" Cc: ak@suse.de, hpa@zytor.com, linux-kernel@vger.kernel.org, tglx@linutronix.de, markus.t.metzger@gmail.com, "Siddha, Suresh B" , roland@redhat.com, akpm@linux-foundation.org, mtk.manpages@gmail.com, Alan Stern Subject: Re: x86, ptrace: support for branch trace store(BTS) Message-ID: <20071213102939.GS8977@elte.hu> References: <20071210123809.A14251@sedona.ch.intel.com> <20071210202052.GA26002@elte.hu> <029E5BE7F699594398CA44E3DDF5544401130A1E@swsmsx413.ger.corp.intel.com> <20071211145301.GA19427@elte.hu> <029E5BE7F699594398CA44E3DDF554440115D3C5@swsmsx413.ger.corp.intel.com> <20071212110330.GD1611@elte.hu> <029E5BE7F699594398CA44E3DDF554440115D6DC@swsmsx413.ger.corp.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <029E5BE7F699594398CA44E3DDF554440115D6DC@swsmsx413.ger.corp.intel.com> User-Agent: Mutt/1.5.17 (2007-11-01) X-ELTE-VirusStatus: clean X-ELTE-SpamScore: -1.5 X-ELTE-SpamLevel: X-ELTE-SpamCheck: no X-ELTE-SpamVersion: ELTE 2.0 X-ELTE-SpamCheck-Details: score=-1.5 required=5.9 tests=BAYES_00 autolearn=no SpamAssassin version=3.2.3 -1.5 BAYES_00 BODY: Bayesian spam probability is 0 to 1% [score: 0.0000] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1190 Lines: 26 * Metzger, Markus T wrote: > Users who want to process that huge amount of data would be better off > using a file-based approach (well, if it cannot be held in physical > memory, they will spend most of their time swapping, anyway). Those > users would typically wait for the 'buffer full' event and drain the > buffer into a file - whether this is the real buffer or a bigger > virtual buffer. > > The two-buffer approach would only benefit users who want to hold the > full profile in memory - or who want to stall the debuggee until they > processed or somehow compressed the data collected so far. Those > approaches would not scale for very big profiles. The small profile > cases would already be covered with a reasonably big real buffer. well, the two-buffer approach would just be a general API with no limitations. It would make the internal buffer mostly a pure performance detail. Ingo -- 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/