From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andrew Gallatin Subject: Re: CPU utilization increased in 2.6.27rc Date: Wed, 13 Aug 2008 11:06:11 -0400 Message-ID: <48A2F863.7040402@myri.com> References: <48A23137.2010107@myri.com> <20080812.180535.99302127.davem@davemloft.net> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org To: David Miller Return-path: Received: from mailbox2.myri.com ([64.172.73.26]:1917 "EHLO myri.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1754548AbYHMPGP (ORCPT ); Wed, 13 Aug 2008 11:06:15 -0400 In-Reply-To: <20080812.180535.99302127.davem@davemloft.net> Sender: netdev-owner@vger.kernel.org List-ID: David Miller wrote: > From: Andrew Gallatin > Date: Tue, 12 Aug 2008 20:56:23 -0400 > >> According to oprofile, the system is spending a lot of >> time in __qdisc_run() when sending on the 1GbE forcedeth >> interface: > > What does the profile look like beforehand? The qdisc stuff is gone, and nearly everything is in the noise. Beforehand, we're at ~15% CPU. Here is the first page or so from opreport -l from immediately prior: 7566 6.4373 vmlinux _raw_spin_lock 5894 5.0147 oprofiled (no symbols) 4136 3.5190 ehci_hcd (no symbols) 3965 3.3735 vmlinux handle_IRQ_event 3333 2.8358 vmlinux tcp_ack 2952 2.5116 vmlinux __copy_skb_header 2869 2.4410 vmlinux default_idle 2702 2.2989 vmlinux nv_rx_process_optimized 2511 2.1364 vmlinux nv_start_xmit_optimized 2310 1.9654 vmlinux sk_run_filter 2157 1.8352 vmlinux kmem_cache_alloc 2139 1.8199 vmlinux IRQ0x69_interrupt 1797 1.5289 vmlinux nv_nic_irq_optimized 1796 1.5281 vmlinux kmem_cache_free 1784 1.5179 vmlinux kfree 1690 1.4379 vmlinux _raw_spin_unlock 1594 1.3562 vmlinux tcp_sendpage 1578 1.3426 vmlinux __tcp_push_pending_frames 1576 1.3409 vmlinux packet_rcv_spkt 1560 1.3273 vmlinux __inet_lookup_established 1558 1.3256 vmlinux nv_tx_done_optimized [ On this system, forcedeth shares an irq with ehci_hcd, so that's why that is so high.] Drew