From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932584Ab0JAM7f (ORCPT ); Fri, 1 Oct 2010 08:59:35 -0400 Received: from mail-fx0-f46.google.com ([209.85.161.46]:53558 "EHLO mail-fx0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932466Ab0JAM7d (ORCPT ); Fri, 1 Oct 2010 08:59:33 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=subject:from:to:cc:in-reply-to:references:content-type:date :message-id:mime-version:x-mailer:content-transfer-encoding; b=MMxO+CXXNhPkVk30hqWMwqg12CD+NN5VLT/lD7O0C/uFGORSuFrr8VVULAb9mZEhfM z7mXodCLM/oyNSfTrWfah1Z2w5+wgvMi5qqaWt+1KbSzKTlo0BkbrwUDT0nnedoTVLry k7DVVgZFFwWiUt7nS5klpOn4k202HNAn46lvk= Subject: Re: Packet time delays on multi-core systems From: Eric Dumazet To: Alexey Vlasov Cc: Linux Kernel Mailing List , netdev In-Reply-To: <20101001101650.GD4094@beaver.vrungel.ru> References: <20100929191851.GC86786@beaver.vrungel.ru> <1285796721.5211.156.camel@edumazet-laptop> <20100930062419.GD86786@beaver.vrungel.ru> <1285828432.5211.812.camel@edumazet-laptop> <20100930122321.GA1575@beaver.vrungel.ru> <1285850669.2615.426.camel@edumazet-laptop> <20100930173732.GB4094@beaver.vrungel.ru> <1285869782.2615.920.camel@edumazet-laptop> <20100930181556.GC4094@beaver.vrungel.ru> <1285872765.2615.1008.camel@edumazet-laptop> <20101001101650.GD4094@beaver.vrungel.ru> Content-Type: text/plain; charset="UTF-8" Date: Fri, 01 Oct 2010 14:59:26 +0200 Message-ID: <1285937966.2641.117.camel@edumazet-laptop> Mime-Version: 1.0 X-Mailer: Evolution 2.30.3 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Le vendredi 01 octobre 2010 à 14:16 +0400, Alexey Vlasov a écrit : > I have also found that: > 1. rx overruns is increasing. > 2. rx_queue_drop_packet_count is increasing. So you flood machine with packets, its not an idle one ? I thought you were doing experiments with light trafic. > # ethtool -S eth0 | grep drop > tx_dropped: 0 > rx_queue_drop_packet_count: 1260743751 > dropped_smbus: 0 > rx_queue_0_drops: 0 > rx_queue_1_drops: 0 > rx_queue_2_drops: 0 > rx_queue_3_drops: 0 > ethtool -S eth0 (full output, not small parts) > 3. By sending SYN-packets by hping, RST packet doesn't send, but I don't know may > be it is just some feature in 2.6.32. > newbox # hping -c 1 -S -p 80 111.111.111.111 > HPING 111.111.111.111 (eth0 111.111.111.111): S set, 40 headers + 0 data bytes > len=46 ip=111.111.111.111 ttl=58 DF id=11471 sport=80 flags=SA seq=0 win=65535 rtt=99.0 ms > > --- 111.111.111.111 hping statistic --- > 1 packets tramitted, 1 packets received, 0% packet loss > round-trip min/avg/max = 99.0/99.0/99.0 ms > > 13:59:07.439528 IP newbox.2777 > 111.111.111.111.80: S 345595033:345595033(0) win 512 > 13:59:07.439626 IP 111.111.111.111.80 > newbox.2777: S 1178827395:1178827395(0) ack 345595034 win 65535 > 13:59:10.439368 IP 111.111.111.111.80 > newbox.2777: S 1178827395:1178827395(0) ack 345595034 win 65535 > 13:59:16.439313 IP 111.111.111.111.80 > newbox.2777: S 1178827395:1178827395(0) ack 345595034 win 65535 > 13:59:28.439206 IP 111.111.111.111.80 > newbox.2777: S 1178827395:1178827395(0) ack 345595034 win 65535 > > As a result I got doubles: Are you playing with trafic shaping ? tc -s -d qdisc > DUP! len=46 ip=111.111.111.111 ttl=58 DF id=27454 sport=80 flags=SA seq=0 win=65535 rtt=3137.8 ms > > Example of another TCP-session from 2.6.28 kernel: > oldbox # hping -c 1 -S -p 80 111.111.111.111 > HPING 111.111.111.111 (eth0 111.111.111.111): S set, 40 headers + 0 data bytes > len=46 ip=111.111.111.111 ttl=58 DF id=53180 sport=80 flags=SA seq=0 win=65535 rtt=2.9 ms > > --- 111.111.111.111 hping statistic --- > 1 packets tramitted, 1 packets received, 0% packet loss > round-trip min/avg/max = 2.9/2.9/2.9 ms > > 14:01:45.225136 IP oldbox.2776 > 111.111.111.111.80: S 1983626200:1983626200(0) win 512 > 14:01:45.225288 IP 111.111.111.111.80 > oldbox.2776: S 3796385036:3796385036(0) ack 1983626201 win 65535 > 14:01:45.227990 IP oldbox.2776 > 111.111.111.111.80: R 1983626201:1983626201(0) win 0 >