From mboxrd@z Thu Jan 1 00:00:00 1970 From: alekcejk@googlemail.com Subject: Re: Re: limited network bandwidth with 3.2.x kernels Date: Mon, 13 Feb 2012 23:16:55 +0200 Message-ID: <3724891.xPvvFc3DxN@localhost.localdomain> References: <8633039.fHPLx6GNq3@localhost.localdomain> <1329164293.2523.0.camel@edumazet-laptop> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: QUOTED-PRINTABLE To: Eric Dumazet , netdev@vger.kernel.org Return-path: Received: from mail-bk0-f46.google.com ([209.85.214.46]:59092 "EHLO mail-bk0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755923Ab2BMVRL convert rfc822-to-8bit (ORCPT ); Mon, 13 Feb 2012 16:17:11 -0500 Received: by bkcjm19 with SMTP id jm19so4908946bkc.19 for ; Mon, 13 Feb 2012 13:17:10 -0800 (PST) In-Reply-To: <1329164293.2523.0.camel@edumazet-laptop> Sender: netdev-owner@vger.kernel.org List-ID: =D0=92 =D1=81=D0=BE=D0=BE=D0=B1=D1=89=D0=B5=D0=BD=D0=B8=D0=B8 =D0=BE=D1= =82 =D0=9F=D0=BE=D0=BD=D0=B5=D0=B4=D0=B5=D0=BB=D1=8C=D0=BD=D0=B8=D0=BA = 13 =D1=84=D0=B5=D0=B2=D1=80=D0=B0=D0=BB=D1=8F 2012 21:18:13 =D0=B2=D1=8B= =D0=BD=D0=B0=D0=BF=D0=B8=D1=81=D0=B0=D0=BB=D0=B8: > Le lundi 13 f=C3=A9vrier 2012 =C3=A0 22:04 +0200, alekcejk@googlemail= =2Ecom a >=20 > =C3=A9crit : > > Hi, > >=20 > > I noticed that with 3.2.x kernels download speed from some internet= resources > > became about half of speed that was with previous kernels (3.1 and = older). > > I tested Fedora 15 kernels 2.6.41.10 =3D 3.1.10 and 2.6.42.3 =3D 3.= 2.3 > > (many times rebooted for testing with first and second kernels). > > See bug https://bugzilla.redhat.com/show_bug.cgi?id=3D789659 > >=20 > > lsmod: > > Module Size Used by > > nvidia 10778232 40 > > i2c_core 28123 1 nvidia > > 8139too 32490 0 > > mii 13311 1 8139too > >=20 > > dmesg: > > 8139too: 8139too Fast Ethernet driver 0.9.28 > > 8139too 0000:01:02.0: PCI INT A -> GSI 22 (level, low) -> IRQ 22 > > 8139too 0000:01:02.0: eth0: RealTek RTL8139 at , IRQ 22 > > 8139too 0000:01:02.0: eth0: link up, 100Mbps, full-duplex, lpa 0x41= E1 > >=20 > > For testing I selected fastest for me download mirrors of FreeBSD a= nd Ubuntu, > > also I tested download speed from site speedtest.tele2.net. > >=20 > > For these sites download speed with 3.1 kernels (and older) is abou= t 11 MB/s > > but with 3.2.x kernels - limited 5.5 MB/s and for some sites still = approximately > > the same as with 3.1 kernels (see bug mentioned above). >=20 > MB/s means MBytes or Mbits ? MB means MegaBytes. This should explain it: =46reeBSD-8.2-RELEASE-i386-dvd1.iso.xz size 2066424512 bytes (1.9 G) do= wnloaded with both kernels: kernel 3.1.10: saved in 3m 31s 9,32 Megabytes/second - average speed, = 11,1 Megabytes/second maximum kernel 3.2.3: saved in 5m 56s 5,54 Megabytes/second - average speed, 5,= 64 Megabytes/s - maximum speed >=20 > > Also I want to pay attention that limited speed stays constant - al= ways > > 5.5 MB/s with straight line on traffic plotter as if was network ba= ndwidth shaping. > > With 3.1 kernels this never happens - speed can vary in some ranges > > but at maximum it is about 11 MB/s, no limitations such as 5.5 MB/s= =2E >=20 > Could you post "netstat -s" result ? "netstat -s" just after system started and download finished kernel 3.1.10: Ip: 1472431 total packets received 0 forwarded 0 incoming packets discarded 1469765 incoming packets delivered 755430 requests sent out 1 outgoing packets dropped Icmp: 0 ICMP messages received 0 input ICMP message failed. ICMP input histogram: 1 ICMP messages sent 0 ICMP messages failed ICMP output histogram: echo request: 1 IcmpMsg: OutType8: 1 Tcp: 4 active connections openings 0 passive connection openings 0 failed connection attempts 0 connection resets received 0 connections established 1469723 segments received 755378 segments send out 0 segments retransmited 0 bad segments received. 32997 resets sent Udp: 35 packets received 0 packets to unknown port received. 0 packet receive errors 52 packets sent 0 receive buffer errors 0 send buffer errors UdpLite: TcpExt: 1 TCP sockets finished time wait in fast timer 22 delayed acks sent 1448 packets directly received from backlog 1429173 packets header predicted 1 packets header predicted and directly queued to user 2 acknowledgments not containing data received 18 predicted acknowledgments 0 TCP data loss events 1 connections reset due to unexpected data IPReversePathFilter: 47 IpExt: InNoRoutes: 218 InMcastPkts: 2 InBcastPkts: 46 OutBcastPkts: 17 InOctets: 2157119711 OutOctets: 38981662 InMcastOctets: 56 InBcastOctets: 3704 OutBcastOctets: 768 kernel 3.2.3:=20 Ip: 1487136 total packets received 0 forwarded 0 incoming packets discarded 1482687 incoming packets delivered 769964 requests sent out 1 outgoing packets dropped Icmp: 0 ICMP messages received 0 input ICMP message failed. ICMP input histogram: 1 ICMP messages sent 0 ICMP messages failed ICMP output histogram: echo request: 1 IcmpMsg: OutType8: 1 Tcp: 2 active connections openings 0 passive connection openings 0 failed connection attempts 0 connection resets received 0 connections established 1482636 segments received 769905 segments send out 0 segments retransmited 0 bad segments received. 55530 resets sent Udp: 42 packets received 0 packets to unknown port received. 0 packet receive errors 59 packets sent 0 receive buffer errors 0 send buffer errors UdpLite: TcpExt: 1 TCP sockets finished time wait in fast timer 15 delayed acks sent 1425598 packets header predicted 1 acknowledgments not containing data received 9 predicted acknowledgments 0 TCP data loss events IPReversePathFilter: 48 IpExt: InNoRoutes: 235 InMcastPkts: 4 InBcastPkts: 47 OutBcastPkts: 17 InOctets: 2143692697 OutOctets: 39392421 InMcastOctets: 112 InBcastOctets: 3941 OutBcastOctets: 768