From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1030358AbWGFRh0 (ORCPT ); Thu, 6 Jul 2006 13:37:26 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1030360AbWGFRhZ (ORCPT ); Thu, 6 Jul 2006 13:37:25 -0400 Received: from liaag2ag.mx.compuserve.com ([149.174.40.158]:8113 "EHLO liaag2ag.mx.compuserve.com") by vger.kernel.org with ESMTP id S1030358AbWGFRhY (ORCPT ); Thu, 6 Jul 2006 13:37:24 -0400 Date: Thu, 6 Jul 2006 13:30:14 -0400 From: Chuck Ebbert <76306.1226@compuserve.com> Subject: Re: [PATCH 10/17] 2.6.17.1 perfmon2 patch for review: PMU context switch To: "eranian@hpl.hp.com" Cc: Andi Kleen , linux-kernel Message-ID: <200607061333_MC3-1-C44C-96D1@compuserve.com> MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org In-Reply-To: <20060704152857.GA6999@frankl.hpl.hp.com> On Tue, 4 Jul 2006 08:28:57 -0700, Stephan Eranian wrote: > Here is what I get on my dual 2.4GHz Opteron 250: > > booted with idle=halt > $ pfmon --us-c -ecpu_clk_unhalted,interrupts_masked_cycles_with_interrupt_pending,interrupts_masked_cycles,cycles_no_fpu_ops_retired -k --system-wide -t 10 > > CPU0 11,356,210 CPU_CLK_UNHALTED > CPU0 0 INTERRUPTS_MASKED_CYCLES_WITH_INTERRUPT_PENDING > CPU0 3,836,107 INTERRUPTS_MASKED_CYCLES > CPU0 23,910,784,532 CYCLES_NO_FPU_OPS_RETIRED > CPU1 19,303,632 CPU_CLK_UNHALTED > CPU1 0 INTERRUPTS_MASKED_CYCLES_WITH_INTERRUPT_PENDING > CPU1 13,942,265 INTERRUPTS_MASKED_CYCLES > CPU1 23,911,872,654 CYCLES_NO_FPU_OPS_RETIRED So it looks like your Opteron continues to count CYCLES_NO_FPU_OPS_RETIRED at full clock speed even when halted. My Turion appears to slow down to ~40 MHz when halted and counts those events at that speed. Using idle=poll shows no slowdown, as expected, and unhalted clocks equals cycles_no_fpu_ops_retired. -- Chuck "You can't read a newspaper if you can't read." --George W. Bush