From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758617AbZA2DnR (ORCPT ); Wed, 28 Jan 2009 22:43:17 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753310AbZA2DnA (ORCPT ); Wed, 28 Jan 2009 22:43:00 -0500 Received: from fgwmail7.fujitsu.co.jp ([192.51.44.37]:50525 "EHLO fgwmail7.fujitsu.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753003AbZA2Dm7 (ORCPT ); Wed, 28 Jan 2009 22:42:59 -0500 From: KOSAKI Motohiro To: Mathieu Desnoyers Subject: Re: [ltt-dev] LTTng 0.87 improved page fault tracing Cc: kosaki.motohiro@jp.fujitsu.com, ltt-dev@lists.casi.polymtl.ca, linux-kernel@vger.kernel.org In-Reply-To: <20090127210203.GA13478@Krystal> References: <20090127210203.GA13478@Krystal> Message-Id: <20090129123827.A959.KOSAKI.MOTOHIRO@jp.fujitsu.com> MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit X-Mailer: Becky! ver. 2.42 [ja] Date: Thu, 29 Jan 2009 12:42:55 +0900 (JST) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi interesting.. > I just combined the 4 page fault handler events that were in the tracing > hot path of LTTng into 2 : > > kernel page_fault_entry > kernel page_fault_exit > > They take as parameter the combination of what was available in the > trap_entry/exit events and handle_mm_fault entry/exit events. This > should lessen the performance impact of the tracer when it's active. > I did the related modifications in LTTV 0.12.8. Just question. As far as I know, customer has two different requeremtn of the page fault. (1) collect number of all page fault -> if it is too large, too many interrupt decrease performance. (2) collect number of major page fault -> major page fault indicate to increase random access I/O, then, some customer want to collect major page fault (don't include minor page fault) Is this patch fill (2) requirement?