Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S965160AbVKPBxL (ORCPT ); Tue, 15 Nov 2005 20:53:11 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S965161AbVKPBxK (ORCPT ); Tue, 15 Nov 2005 20:53:10 -0500 Received: from mail06.syd.optusnet.com.au ([211.29.132.187]:1455 "EHLO mail06.syd.optusnet.com.au") by vger.kernel.org with ESMTP id S965160AbVKPBxJ (ORCPT ); Tue, 15 Nov 2005 20:53:09 -0500 MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Message-ID: <17274.37097.609985.45439@wombat.chubb.wattle.id.au> Date: Wed, 16 Nov 2005 12:52:41 +1100 From: Peter Chubb To: nagar@watson.ibm.com Cc: Peter Chubb , Andrew Morton , linux-kernel@vger.kernel.org, Ingo Molnar , Andi Kleen Subject: Re: [Patch 1/4] Delay accounting: Initialization In-Reply-To: <437A8FED.3080508@watson.ibm.com> References: <43796596.2010908@watson.ibm.com> <20051114202017.6f8c0327.akpm@osdl.org> <17274.34333.348600.111728@wombat.chubb.wattle.id.au> <437A8FED.3080508@watson.ibm.com> X-Mailer: VM 7.17 under 21.4 (patch 17) "Jumbo Shrimp" XEmacs Lucid Comments: Hyperbole mail buttons accepted, v04.18. X-Face: GgFg(Z>fx((4\32hvXq<)|jndSniCH~~$D)Ka:P@e@JR1P%Vr}EwUdfwf-4j\rUs#JR{'h# !]])6%Jh~b$VA|ALhnpPiHu[-x~@<"@Iv&|%R)Fq[[,(&Z'O)Q)xCqe1\M[F8#9l8~}#u$S$Rm`S9% \'T@`:&8>Sb*c5d'=eDYI&GF`+t[LfDH="MP5rwOO]w>ALi7'=QJHz&y&C&TE_3j! Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1457 Lines: 36 >>>>> "Shailabh" == Shailabh Nagar writes: Shailabh> Peter Chubb wrote: >>>>>>> "Andrew" == Andrew Morton writes: >> Andrew> Shailabh Nagar wrote: >> >>>> + *ts = sched_clock(); >> Andrew> I'm not sure that it's kosher to use sched_clock() for Andrew> fine-grained timestamping like this. Ingo had issues with it Andrew> last time this happened? >> It wasn't Ingo, it was Andi Kleen... for my Microstate Accounting >> patches, which do very similar things to Shailabh's patchsetm, but >> using /proc and a system call instead (following Solaris's lead) >> Shailabh> Were these the comments from Andi to which you refer: Shailabh> http://www.uwsg.indiana.edu/hypermail/linux/kernel/0503.1/1237.html Shailabh> The objections to microstate overhead seemed to stem from Shailabh> the syscall overhead, not use of sched_clock() per se. The objection was to the use of rdtsc (which is sched_clock() on platforms that have rdtsc) in fastpaths. Anyway, I think it's time to repost the microstate patches. -- Dr Peter Chubb http://www.gelato.unsw.edu.au peterc AT gelato.unsw.edu.au The technical we do immediately, the political takes *forever* - 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/