Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754211AbYKQTn7 (ORCPT ); Mon, 17 Nov 2008 14:43:59 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752240AbYKQTnt (ORCPT ); Mon, 17 Nov 2008 14:43:49 -0500 Received: from gw1.cosmosbay.com ([86.65.150.130]:39464 "EHLO gw1.cosmosbay.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751982AbYKQTns convert rfc822-to-8bit (ORCPT ); Mon, 17 Nov 2008 14:43:48 -0500 Message-ID: <4921C947.9070609@cosmosbay.com> Date: Mon, 17 Nov 2008 20:43:03 +0100 From: Eric Dumazet User-Agent: Thunderbird 2.0.0.17 (Windows/20080914) MIME-Version: 1.0 To: David Miller CC: mingo@elte.hu, torvalds@linux-foundation.org, rjw@sisk.pl, linux-kernel@vger.kernel.org, kernel-testers@vger.kernel.org, cl@linux-foundation.org, efault@gmx.de, a.p.zijlstra@chello.nl, shemminger@vyatta.com Subject: Re: [Bug #11308] tbench regression on each kernel release from 2.6.22 -> 2.6.28 References: <20081117182320.GA26844@elte.hu> <20081117184951.GA5585@elte.hu> <20081117.113936.81699150.davem@davemloft.net> In-Reply-To: <20081117.113936.81699150.davem@davemloft.net> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 8BIT X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-1.6 (gw1.cosmosbay.com [0.0.0.0]); Mon, 17 Nov 2008 20:43:07 +0100 (CET) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3133 Lines: 87 David Miller a ?crit : > From: Ingo Molnar > Date: Mon, 17 Nov 2008 19:49:51 +0100 > >> * Ingo Molnar wrote: >> >> 4> The place for the sock_rfree() hit looks a bit weird, and i'll >>> investigate it now a bit more to place the real overhead point >>> properly. (i already mapped the test-bit overhead: that comes from >>> napi_disable_pending()) >> ok, here's a new set of profiles. (again for tbench 64-thread on a >> 16-way box, with v2.6.28-rc5-19-ge14c8bf and with the kernel config i >> posted before.) > > Again, do a non-NMI profile and the top (at least for me) > looks like this: > > samples % app name symbol name > 473 6.3928 vmlinux finish_task_switch > 349 4.7169 vmlinux tcp_v4_rcv > 327 4.4195 vmlinux U3copy_from_user > 322 4.3519 vmlinux tl0_linux32 > 178 2.4057 vmlinux tcp_ack > 170 2.2976 vmlinux tcp_sendmsg > 167 2.2571 vmlinux U3copy_to_user > > That tcp_v4_rcv() hit is %98 on the wake_up() call it does. > > Another profile from my tree (net-next-2.6 + some patches), on my machine CPU: Core 2, speed 3000.22 MHz (estimated) Counted CPU_CLK_UNHALTED events (Clock cycles when not halted) with a unit mask of 0x00 (Unhalted core cycles) count 100000 samples % symbol name 223265 9.2711 __copy_user_zeroing_intel 87525 3.6345 __copy_user_intel 73203 3.0398 tcp_sendmsg 53229 2.2103 netif_rx 53041 2.2025 tcp_recvmsg 47241 1.9617 sysenter_past_esp 42888 1.7809 __copy_from_user_ll 40858 1.6966 tcp_transmit_skb 39390 1.6357 __switch_to 37363 1.5515 dst_release 36823 1.5291 __sk_dst_check_get 36050 1.4970 tcp_v4_rcv 35829 1.4878 __do_softirq 32333 1.3426 tcp_rcv_established 30451 1.2645 tcp_clean_rtx_queue 29758 1.2357 ip_queue_xmit 28497 1.1833 __copy_to_user_ll 28119 1.1676 release_sock 25218 1.0472 lock_sock_nested 23701 0.9842 __inet_lookup_established 23463 0.9743 tcp_ack 22989 0.9546 netif_receive_skb 21880 0.9086 sched_clock_cpu 20730 0.8608 tcp_write_xmit 20372 0.8460 ip_rcv 20336 0.8445 local_bh_enable 19153 0.7953 __update_sched_clock 18603 0.7725 skb_release_data 17020 0.7068 local_bh_enable_ip 16932 0.7031 process_backlog 16299 0.6768 ip_finish_output 16279 0.6760 dev_queue_xmit 15858 0.6585 sock_recvmsg 15641 0.6495 native_read_tsc 15454 0.6417 sock_wfree 15366 0.6381 update_curr 14585 0.6056 sys_socketcall 14564 0.6048 __alloc_skb 14519 0.6029 __tcp_select_window 14417 0.5987 tcp_current_mss 14391 0.5976 nf_iterate 14221 0.5905 page_address 14122 0.5864 local_bh_disable -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/