From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([140.186.70.92]:41272) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1RruOh-00041o-49 for qemu-devel@nongnu.org; Mon, 30 Jan 2012 11:48:08 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1RruOX-0000Vc-6H for qemu-devel@nongnu.org; Mon, 30 Jan 2012 11:48:03 -0500 Received: from indium.canonical.com ([91.189.90.7]:60114) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1RruOX-0000Uu-25 for qemu-devel@nongnu.org; Mon, 30 Jan 2012 11:47:53 -0500 Received: from loganberry.canonical.com ([91.189.90.37]) by indium.canonical.com with esmtp (Exim 4.71 #1 (Debian)) id 1RruOV-0007l7-5H for ; Mon, 30 Jan 2012 16:47:51 +0000 Received: from loganberry.canonical.com (localhost [127.0.0.1]) by loganberry.canonical.com (Postfix) with ESMTP id 4ABC52E899C for ; Mon, 30 Jan 2012 16:41:25 +0000 (UTC) MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Date: Mon, 30 Jan 2012 16:30:45 -0000 From: Vincent Autefage <899140@bugs.launchpad.net> Sender: bounces@canonical.com References: <20111202125742.13621.362.malonedeb@soybean.canonical.com> <20120129044901.6982.30037.malone@soybean.canonical.com> Message-Id: <4F26C5C6.2090505@labri.fr> Errors-To: bounces@canonical.com Subject: Re: [Qemu-devel] [Bug 899140] Re: Problem with Linux Kernel Traffic Control Reply-To: Bug 899140 <899140@bugs.launchpad.net> List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Hi, The problem seems to come from the implementation of the Intel e1000 = network cards (which is the default one used by QEMU). If you use another one, the problem does not appear ;) Vince Le 29/01/2012 05:49, Henrique Rodrigues a =C3=A9crit : > Hi guys, > > I'm having the same problem with a ubuntu 11.04 (natty) host. I tried to > set the rate controllers using tc both at the host and inside the guest > i.e.: > > tc qdisc add vnic0 root tbf rate 20mbit burst 20480 latency 50ms (host - = to control the traffic going to the guest vm) and > tc qdisc add eth0 root tbf rate 20mbit burst 20480 latency 50ms (guest) > > And the results are the same reported initially: ~140kbit/sec. I also > tried to use policing filters at the host but I got the same results. > > However, if I use htb I can get reasonable throughputs (~20mbit). I used > these commands (both for host and guest): > > tc qdisc add dev root handle 1: htb default 255 > tc class add dev parent 1: classid 1:1 htb rate 20mbit burst 20480 > tc filter add dev parent 1: prio 255 proto ip u32 match ip src 0.0.= 0.0/0 flowid 1:1 > > It seems that the problem is related with the root qdisc only. Have you > guys found an answer for this? > -- = You received this bug notification because you are a member of qemu- devel-ml, which is subscribed to QEMU. https://bugs.launchpad.net/bugs/899140 Title: Problem with Linux Kernel Traffic Control Status in QEMU: New Bug description: Hi, The last main versions of QEMU (0.14.1, 0.15 and 1.0) have an important p= roblem when running on a Linux distribution which running itself a Traffic = Control (TC) instance. Indeed, when TC is configured with a Token Bucket Filter (TBF) with a par= ticular rate, the effective rate is very slower than the desired one. For instance, lets consider the following configuration : # tc qdisc add dev eth0 root tbf rate 20mbit burst 20k latency 50ms The effective rate will be about 100kbit/s ! (verified with iperf) I've encountered this problem on versions 0.14.1, 0.15 and 1.0 but not wi= th the 0.14.0... In the 0.14.0, we have a rate of 19.2 mbit/s which is quiet normal. I've done the experimentation on several hosts : - Debian 32bit core i7, 4GB RAM - Debian 64bit core i7, 8GB RAM - 3 different high performance servers : Ubuntu 64 bits, 48 AMD Opteron, = 128GB of RAM The problem is always the same... The problem is also seen with a Class Based Queuing (CBQ) in TC. Thanks To manage notifications about this bug go to: https://bugs.launchpad.net/qemu/+bug/899140/+subscriptions