From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.suse.de ([195.135.220.2]:28056 "EHLO mx1.suse.de") by vger.kernel.org with ESMTP id S1752155AbWCJBpP (ORCPT ); Thu, 9 Mar 2006 20:45:15 -0500 From: Andi Kleen Subject: Re: Request for feedback on Generic Timeofday Subsystem (B20) Date: Thu, 9 Mar 2006 19:18:00 +0100 References: <1141695346.11401.39.camel@cog.beaverton.ibm.com> <1141953314.20123.110.camel@cog.beaverton.ibm.com> In-Reply-To: <1141953314.20123.110.camel@cog.beaverton.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200603091918.01155.ak@suse.de> Sender: linux-arch-owner@vger.kernel.org To: john stultz Cc: "Luck, Tony" , linux-arch@vger.kernel.org List-ID: On Friday 10 March 2006 02:15, john stultz wrote: > On an x86-64 AMD server using nopmtimer/clocksource=tsc: > mainline vs TOD > gettimeofday(): 74.2% > clock_gettime(CLOCK_MONOTONIC): 77.4% > clock_gettime(CLOCK_REALTIME): 71.6% > > Hmmmm. I'm heading out of town for the weekend in a few moments, and I'd > really like to re-verify those numbers, but yea, that's a 25% > improvement. Might be too good to be true, but that should get Andi's > attention :) What is clocksource=tsc? It doesn't exist on 64bit kernels. And what are the absolute numbers? And clock_gettime uses a completely different path from gettimeofday so if they have the same percentage your results look somewhat suspicious. -Andi