From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932250AbWFZSAw (ORCPT ); Mon, 26 Jun 2006 14:00:52 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932249AbWFZSAv (ORCPT ); Mon, 26 Jun 2006 14:00:51 -0400 Received: from e2.ny.us.ibm.com ([32.97.182.142]:25529 "EHLO e2.ny.us.ibm.com") by vger.kernel.org with ESMTP id S932228AbWFZSAt (ORCPT ); Mon, 26 Jun 2006 14:00:49 -0400 Message-ID: <44A020CD.30903@watson.ibm.com> Date: Mon, 26 Jun 2006 14:00:45 -0400 From: Shailabh Nagar User-Agent: Mozilla Thunderbird 1.0.7 (Windows/20050923) X-Accept-Language: en-us, en MIME-Version: 1.0 To: Andrew Morton CC: Jay Lan , jlan@engr.sgi.com, balbir@in.ibm.com, csturtiv@sgi.com, linux-kernel@vger.kernel.org Subject: Re: [Patch][RFC] Disabling per-tgid stats on task exit in taskstats References: <44892610.6040001@watson.ibm.com> <20060609010057.e454a14f.akpm@osdl.org> <448952C2.1060708@in.ibm.com> <20060609042129.ae97018c.akpm@osdl.org> <4489EE7C.3080007@watson.ibm.com> <449999D1.7000403@engr.sgi.com> <44999A98.8030406@engr.sgi.com> <44999F5A.2080809@watson.ibm.com> <4499D7CD.1020303@engr.sgi.com> <449C2181.6000007@watson.ibm.com> <20060623141926.b28a5fc0.akpm@osdl.org> <449C6620.1020203@engr.sgi.com> <20060623164743.c894c314.akpm@osdl.org> <449CAA78.4080902@watson.ibm.com> <20060623213912.96056b02.akpm@osdl.org> <449CD4B3.8020300@watson.ibm.com> <44A01A50.1050403@sgi.com> <20060626105548.edef4c64.akpm@osdl.org> In-Reply-To: <20060626105548.edef4c64.akpm@osdl.org> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Andrew Morton wrote: >On Mon, 26 Jun 2006 10:33:04 -0700 >Jay Lan wrote: > > > >>>Will that work for everyone ? >>> >>> >>As long as the per-pid delayacct struct has a pointer to the per-tgid >>data struct and deoes not need to go through the loop on every exit. >> >> > >My brain is wilting, and time is moving along. > >Balbir, are you able to summarise where we stand wrt >per-task-delay-accounting-* now? > > Andrew, I'm maintaining per-task delay accouting and taskstats interface patches so I'll take the liberty to reply :-) >What problem have we identified? How close are we to finding agreeable >solutions to them? > > The main problems identified are: 1. extra sending of per-tgid stats on every thread exit 2. unnecessary send of per-tgid stats when there are no listeners 3. unnecessary linkage of delayacct accumalation into per-tgid stats with sending out of taskstats All three have an acceptable solution. 1. & 3. are going to be addressed in a patch I'm sending out shortly. 2. in a separate patch also being sent out shortly. >My general sense is that there's some rework needed, and that rework will >affect the userspace interfaces, which is a problem for a 2.6.18 merge. > > The rework will affect the number of per-tgid records that userspace sees (fewer), not the format or any of the other details regarding the genetlink interface. Will that be a problem for userspace ? --Shailabh