From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932936AbWFWI2v (ORCPT ); Fri, 23 Jun 2006 04:28:51 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932935AbWFWI2v (ORCPT ); Fri, 23 Jun 2006 04:28:51 -0400 Received: from mail.gmx.de ([213.165.64.21]:59571 "HELO mail.gmx.net") by vger.kernel.org with SMTP id S932936AbWFWI2v (ORCPT ); Fri, 23 Jun 2006 04:28:51 -0400 X-Authenticated: #14349625 Subject: Re: Measuring tools - top and interrupts From: Mike Galbraith To: danial_thom@yahoo.com Cc: Erik Mouw , linux-kernel@vger.kernel.org In-Reply-To: <20060622233744.99206.qmail@web33314.mail.mud.yahoo.com> References: <20060622233744.99206.qmail@web33314.mail.mud.yahoo.com> Content-Type: text/plain Date: Fri, 23 Jun 2006 10:32:23 +0200 Message-Id: <1151051543.11381.43.camel@Homer.TheSimpsons.net> Mime-Version: 1.0 X-Mailer: Evolution 2.4.0 Content-Transfer-Encoding: 7bit X-Y-GMX-Trusted: 0 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 2006-06-22 at 16:37 -0700, Danial Thom wrote: > I'm sorry, but you're being an idiot if you think > that 16K interrupts per second and forwarding 75K > pps generate no cpu load. Its just that simple. > It also means that you've never profiled a kernel > because you don't understand where the loads are > generated. You've probably been on too many lists > with too many people who have no idea what > they're talking about. (what horrid manners) Hm. You may be right about the load average calculation being broken. Below is a 100 second profile sample of my 3GHz P4 handling 15K interrupts per second while receiving a flood ping. My interpretation is that tools should be showing ~10% cpu load rather than zero. Am I'm misinterpreting it? 97574 total 0.0258 89549 default_idle 1017.6023 1734 ioread16 36.8936 1138 ioread8 24.7391 974 rhine_start_tx 1.3994 534 __do_softirq 3.8417 331 handle_IRQ_event 3.2772 223 rhine_interrupt 0.0739 222 memset 7.9286 194 nf_iterate 1.5520 140 local_bh_enable 1.0769 99 __kmalloc 1.0532 92 net_rx_action 0.2000 85 kfree 0.9884 82 skb_release_data 0.6406 77 csum_partial_copy_generic 0.3105 73 ip_push_pending_frames 0.0681 71 __alloc_skb 0.2898 69 kmem_cache_free 1.3529 66 kmem_cache_alloc 1.3750 62 csum_partial 0.2153 61 rt_hash_code 0.4959 61 ip_append_data 0.0253 60 netif_receive_skb 0.0516 58 ip_rcv 0.0471 58 ip_local_deliver 0.0854 58 eth_type_trans 0.2489 55 ip_output 0.0957 52 icmp_reply 0.1187