Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1763457AbXFEG4j (ORCPT ); Tue, 5 Jun 2007 02:56:39 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1761534AbXFEG4c (ORCPT ); Tue, 5 Jun 2007 02:56:32 -0400 Received: from ausmtp04.au.ibm.com ([202.81.18.152]:59345 "EHLO ausmtp04.au.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1760978AbXFEG4b (ORCPT ); Tue, 5 Jun 2007 02:56:31 -0400 Message-ID: <466507B4.2070802@linux.vnet.ibm.com> Date: Tue, 05 Jun 2007 12:20:28 +0530 From: Balbir Singh Reply-To: balbir@linux.vnet.ibm.com Organization: IBM User-Agent: Thunderbird 1.5.0.10 (X11/20070403) MIME-Version: 1.0 To: Andrew Morton CC: Maxim Uvarov , LKML , Shailabh Nagar , Balbir Singh , Jay Lan Subject: Re: [PATCH] Performance Stats: Kernel patch References: <20070530184945.28147.50305.stgit@localhost.localdomain> <20070604121955.734de15e.akpm@linux-foundation.org> In-Reply-To: <20070604121955.734de15e.akpm@linux-foundation.org> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2184 Lines: 67 Andrew Morton wrote: > On Wed, 30 May 2007 18:49:46 +0000 > Maxim Uvarov wrote: > >> +void print_taskstats(struct taskstats *t) >> +{ >> + printf("\n\nTask %15s%15s\n" >> + " %15lu%15lu\n", >> + "voluntary", "nonvoluntary", >> + t->nvcsw, t->nivcsw); >> +} > > print_task_stats versus print_taskstats is a bit confusing, but I guess it > doesn't matter. > > More significantly, the whole idea of calling it "task stats" isn't a good > one: it's far too general. The whole kernel interface is called taskstats, > but the additions here are a tiny part of that. > > Perhaps task_context_switch_rates would be more appropriate, although > rather a lot to type. > I agree, taskstats is the name given to the genetlink interface. > The patch otherwise seems OK. Thoughts: > > - Do we need to increment TASKSTATS_VERSION for this? I forget the rules > there. Any ABI change should result in a version bump. So the bump is ok > > - The lack of context-switch accounting in taskstats is, I think, a > simple oversight. It should have been included on day one. > Yes, it should have been included > There are perhaps other things which _should_ be in taskstats, but we > forgot to add them. Can we think of any such things? > I think it's worth reviewing the data exported. I thought CSA filled out the gaps, but it's definitely worth revisiting. > We shouldn't just toss any old random stuff in there: it should be > things which make sense, and which Unix or Linux accounting traditionally > provides, and it should be something which we expect won't suddenly > become unsupportable if people make internal kernel changes. > Yes, agreed. The interface must also be open for changes to accounting information that might be useful as a result of new features, like containers, etc. -- Warm Regards, Balbir Singh Linux Technology Center IBM, ISTL - 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/