From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755114AbZHDUTb (ORCPT ); Tue, 4 Aug 2009 16:19:31 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754269AbZHDUTa (ORCPT ); Tue, 4 Aug 2009 16:19:30 -0400 Received: from smtp1.linux-foundation.org ([140.211.169.13]:33314 "EHLO smtp1.linux-foundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753988AbZHDUTa (ORCPT ); Tue, 4 Aug 2009 16:19:30 -0400 Date: Tue, 4 Aug 2009 13:18:18 -0700 From: Andrew Morton To: Ingo Molnar Cc: penberg@cs.helsinki.fi, a.p.zijlstra@chello.nl, fweisbec@gmail.com, rostedt@goodmis.org, mel@csn.ul.ie, lwoodman@redhat.com, riel@redhat.com, peterz@infradead.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org Subject: Re: [PATCH 4/4] tracing, page-allocator: Add a postprocessing script for page-allocator-related ftrace events Message-Id: <20090804131818.ee5d4696.akpm@linux-foundation.org> In-Reply-To: <20090804195717.GA5998@elte.hu> References: <1249409546-6343-1-git-send-email-mel@csn.ul.ie> <1249409546-6343-5-git-send-email-mel@csn.ul.ie> <20090804112246.4e6d0ab1.akpm@linux-foundation.org> <20090804195717.GA5998@elte.hu> X-Mailer: Sylpheed version 2.2.4 (GTK+ 2.8.20; i486-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 4 Aug 2009 21:57:17 +0200 Ingo Molnar wrote: > Let me demonstrate these features in action (i've applied the > patches for testing to -tip): So? The fact that certain things can be done doesn't mean that there's a demand for them, nor that anyone will _use_ this stuff. As usual, we're adding tracepoints because we feel we must add tracepoints, not because anyone has a need for the data which they gather. There is some benefit in providing MM developers with some code which they can copy-n-paste for their day-to-day activity. But as I said, they can do that with vmstat too. If we can get rid of vmstat all together (and meminfo) and replace all that with common infrastructure then that would be a good cleanup. But if we end up leaving vmstat and meminfo in place and then adding _another_ statistic gathering mechanism in parallel then we haven't cleaned anything up at all - it just gets worse. I don't really oppose the patches - they're small. But they seem rather useless too. It would be nice to at least partially remove the vmstat/meminfo infrastructure but I don't think we can do that?