From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753407AbXDBIRT (ORCPT ); Mon, 2 Apr 2007 04:17:19 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753396AbXDBIRT (ORCPT ); Mon, 2 Apr 2007 04:17:19 -0400 Received: from rwcrmhc14.comcast.net ([204.127.192.84]:50909 "EHLO rwcrmhc14.comcast.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752940AbXDBIRS (ORCPT ); Mon, 2 Apr 2007 04:17:18 -0400 X-Greylist: delayed 46922 seconds by postgrey-1.27 at vger.kernel.org; Mon, 02 Apr 2007 04:17:18 EDT Message-ID: <4610BC15.5030800@ieee.org> Date: Mon, 02 Apr 2007 04:17:25 -0400 From: Dave Sperry User-Agent: Thunderbird 1.5.0.10 (X11/20070302) MIME-Version: 1.0 To: Ingo Molnar CC: linux-rt-users@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: Poor UDP performance using 2.6.21-rc5-rt5 References: <461004CE.1030009@ieee.org> <20070402072111.GA21356@elte.hu> In-Reply-To: <20070402072111.GA21356@elte.hu> 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 Ingo Molnar wrote: > * Dave Sperry wrote: > >> I have a dual core Opteron machine that exhibits poor UDP performance >> (RT consumes more than 2X cpu) with the 2.6.21-rc5-rt5 as compared to >> 2.6.21-rc5. Top shows the IRQ handler consuming a lot of CPU. > > update: even with acpi_pm clocksource on vanilla i can reproduce similar > overhead using netperf. > > Ingo > Hi Ingo I checked the clock source and in both the vanilla and rt cases and they were both acpi_pm Here's the oprofile for my vanilla case: CPU: AMD64 processors, speed 2211.37 MHz (estimated) Counted CPU_CLK_UNHALTED events (Cycles outside of halt state) with a unit mask of 0x00 (No unit mask) count 100000 samples % image name app name symbol name 36264 18.2763 forcedeth.ko forcedeth nv_nic_irq_optimized 25602 12.9029 vmlinux vmlinux spurious_interrupt 10067 5.0736 forcedeth.ko forcedeth nv_start_xmit_optimized 8671 4.3700 vmlinux vmlinux unregister_kprobe 8270 4.1679 vmlinux vmlinux ctrl_dumpfamily 8042 4.0530 vmlinux vmlinux expand_files 5064 2.5521 vmlinux vmlinux kfree 4365 2.1999 libc-2.5.so libc-2.5.so __sendto_nocancel 4067 2.0497 vmlinux vmlinux unix_bind 4010 2.0210 vmlinux vmlinux bad_gs 3929 1.9801 vmlinux vmlinux __alloc_skb 3859 1.9449 vmlinux vmlinux stack_segment 3107 1.5659 vmlinux vmlinux __find_get_block 2816 1.4192 vmlinux vmlinux vfs_create 2611 1.3159 vmlinux vmlinux ide_end_drive_cmd 2604 1.3124 vmlinux vmlinux ide_end_request 2560 1.2902 vmlinux vmlinux find_get_page 2458 1.2388 vmlinux vmlinux hrtimer_run_queues 2456 1.2378 vmlinux vmlinux get_wchan 2403 1.2111 forcedeth.ko forcedeth nv_tx_done_optimized 2231 1.1244 vmlinux vmlinux do_sys_poll Any thoughts? Thanks Dave