From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from sc8-sf-mx2-b.sourceforge.net ([10.3.1.92] helo=mail.sourceforge.net) by sc8-sf-list1-new.sourceforge.net with esmtp (Exim 4.43) id 1Hy47h-0000t5-AD for user-mode-linux-devel@lists.sourceforge.net; Tue, 12 Jun 2007 04:01:17 -0700 Received: from winmain.rutgers.edu ([128.6.230.194] helo=liman.rutgers.edu) by mail.sourceforge.net with esmtps (TLSv1:AES256-SHA:256) (Exim 4.44) id 1Hy47g-0003m3-P9 for user-mode-linux-devel@lists.sourceforge.net; Tue, 12 Jun 2007 04:01:17 -0700 From: "George Hadjichristofi" Date: Tue, 12 Jun 2007 07:01:05 -0400 Message-ID: <010701c7ace0$f98b0d80$d8c8a8c0@angel4> MIME-Version: 1.0 Subject: [uml-devel] UDP vs. TCP performance over UML List-Id: The user-mode Linux development list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: multipart/mixed; boundary="===============1367514456==" Sender: user-mode-linux-devel-bounces@lists.sourceforge.net Errors-To: user-mode-linux-devel-bounces@lists.sourceforge.net To: user-mode-linux-devel@lists.sourceforge.net Cc: 'shruti singhal' This is a multi-part message in MIME format. --===============1367514456== Content-Type: multipart/alternative; boundary="----=_NextPart_000_0108_01C7ACBF.72796D80" This is a multi-part message in MIME format. ------=_NextPart_000_0108_01C7ACBF.72796D80 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Dear All, We are doing some UML performance testing and we are getting some non-sensible UDP statistics. We have deployed the following network of two nodes: A--------B Node A is connected to node B via a wired link (100 Mbps) and node A is running one UML instance. We used the Iperf traffic generator to execute performance measurements for both TCP and UDP. Measurements: When we use TCP the throughput is 100 Mbps from the UML instance of node A to the host kernel of node B and 100 Mbps from the host kernel of node A to the host kernel of node B. However, when we use UDP the throughput is only 26 Mbps from the UML instance on node A to the host kernel of node B, but 100 Mbps from the host kernel of node A to the host kernel of node B. We also notice that a large number of packets were dropped in the case of UDP over UML. What is the reason that UDP throughput is so much lower than TCP? Why are packets being dropped given that Iperf is blocking? We appreciate any guidance on this matter. Regards, George Hadjichristofi WINLAB, Rutgers University ------=_NextPart_000_0108_01C7ACBF.72796D80 Content-Type: text/html; charset="us-ascii" Content-Transfer-Encoding: quoted-printable

Dear All,

We are doing some UML performance testing and we are = getting some non-sensible UDP statistics.

We have deployed the following network of two = nodes:

A--------B

Node A is connected to node B via a wired link (100 = Mbps) and node A is running one UML instance.

We used the Iperf traffic generator to execute = performance measurements for both TCP and UDP.

Measurements:

When we use TCP the throughput is 100 Mbps from = the UML instance of node A to the host kernel of node B and 100 Mbps from = the host kernel of node A to the host kernel of node B. However, when we = use UDP the throughput is only 26 Mbps from the UML instance on node A to the = host kernel of node B, but 100 Mbps from the host kernel of node A to the = host kernel of node B. We also notice that a large number of packets = were dropped in the case of UDP over UML.

What is the reason that UDP throughput is so much = lower than TCP?

Why are packets being dropped given that Iperf is = blocking?

We appreciate any guidance on this = matter.

Regards,

George Hadjichristofi

WINLAB, Rutgers University

------=_NextPart_000_0108_01C7ACBF.72796D80-- --===============1367514456== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline ------------------------------------------------------------------------- This SF.net email is sponsored by DB2 Express Download DB2 Express C - the FREE version of DB2 express and take control of your XML. No limits. Just data. Click to get it now. http://sourceforge.net/powerbar/db2/ --===============1367514456== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ User-mode-linux-devel mailing list User-mode-linux-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/user-mode-linux-devel --===============1367514456==-- From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from sc8-sf-mx2-b.sourceforge.net ([10.3.1.92] helo=mail.sourceforge.net) by sc8-sf-list1-new.sourceforge.net with esmtp (Exim 4.43) id 1Hy7un-0008SW-94 for user-mode-linux-devel@lists.sourceforge.net; Tue, 12 Jun 2007 08:04:14 -0700 Received: from saraswathi.solana.com ([198.99.130.12]) by mail.sourceforge.net with esmtps (TLSv1:AES256-SHA:256) (Exim 4.44) id 1Hy7ul-0002s9-OC for user-mode-linux-devel@lists.sourceforge.net; Tue, 12 Jun 2007 08:04:13 -0700 Date: Tue, 12 Jun 2007 11:04:05 -0400 From: Jeff Dike Message-ID: <20070612150405.GA7102@c2.user-mode-linux.org> References: <010701c7ace0$f98b0d80$d8c8a8c0@angel4> Mime-Version: 1.0 Content-Disposition: inline In-Reply-To: <010701c7ace0$f98b0d80$d8c8a8c0@angel4> Subject: Re: [uml-devel] UDP vs. TCP performance over UML List-Id: The user-mode Linux development list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: user-mode-linux-devel-bounces@lists.sourceforge.net Errors-To: user-mode-linux-devel-bounces@lists.sourceforge.net To: George Hadjichristofi Cc: 'shruti singhal' , user-mode-linux-devel@lists.sourceforge.net On Tue, Jun 12, 2007 at 07:01:05AM -0400, George Hadjichristofi wrote: > When we use TCP the throughput is 100 Mbps from the UML instance of node A > to the host kernel of node B and 100 Mbps from the host kernel of node A to > the host kernel of node B. However, when we use UDP the throughput is only > 26 Mbps from the UML instance on node A to the host kernel of node B, but > 100 Mbps from the host kernel of node A to the host kernel of node B. We > also notice that a large number of packets were dropped in the case of UDP > over UML. At what interface are the packets being dropped? Jeff -- Work email - jdike at linux dot intel dot com ------------------------------------------------------------------------- This SF.net email is sponsored by DB2 Express Download DB2 Express C - the FREE version of DB2 express and take control of your XML. No limits. Just data. Click to get it now. http://sourceforge.net/powerbar/db2/ _______________________________________________ User-mode-linux-devel mailing list User-mode-linux-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/user-mode-linux-devel From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from sc8-sf-mx1-b.sourceforge.net ([10.3.1.91] helo=mail.sourceforge.net) by sc8-sf-list1-new.sourceforge.net with esmtp (Exim 4.43) id 1HyGmq-00022u-4l for user-mode-linux-devel@lists.sourceforge.net; Tue, 12 Jun 2007 17:32:36 -0700 Received: from winmain.rutgers.edu ([128.6.230.194] helo=liman.rutgers.edu) by mail.sourceforge.net with esmtps (TLSv1:AES256-SHA:256) (Exim 4.44) id 1HyGmo-0007yI-F3 for user-mode-linux-devel@lists.sourceforge.net; Tue, 12 Jun 2007 17:32:36 -0700 From: "George Hadjichristofi" References: <010701c7ace0$f98b0d80$d8c8a8c0@angel4> <20070612150405.GA7102@c2.user-mode-linux.org> Date: Tue, 12 Jun 2007 20:32:15 -0400 Message-ID: <036601c7ad52$4b0c76a0$d8c8a8c0@angel4> MIME-Version: 1.0 In-Reply-To: <20070612150405.GA7102@c2.user-mode-linux.org> Subject: Re: [uml-devel] UDP vs. TCP performance over UML List-Id: The user-mode Linux development list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: user-mode-linux-devel-bounces@lists.sourceforge.net Errors-To: user-mode-linux-devel-bounces@lists.sourceforge.net To: 'Jeff Dike' , 'George Hadjichristofi' Cc: 'shruti singhal' , user-mode-linux-devel@lists.sourceforge.net Hi Jeff, We took some more measurements. This is what we have: A to B with UML: 46Mbps with UDP, 147Mbps with TCP A to B from Host kernel: 285 Mbps for both UDP and TCP In the case of A to B (with UML on A) there are packets dropped. Based on Ifconfig on the host kernel the packets seem to drop between tap0 and eth0 on the host kernel. (i.e., the number of packets on tap0 is higher than eth0). Hope that was clear enough. Thank you, George -----Original Message----- From: user-mode-linux-devel-bounces@lists.sourceforge.net [mailto:user-mode-linux-devel-bounces@lists.sourceforge.net] On Behalf Of Jeff Dike Sent: Tuesday, June 12, 2007 11:04 AM To: George Hadjichristofi Cc: 'shruti singhal'; user-mode-linux-devel@lists.sourceforge.net Subject: Re: [uml-devel] UDP vs. TCP performance over UML On Tue, Jun 12, 2007 at 07:01:05AM -0400, George Hadjichristofi wrote: > When we use TCP the throughput is 100 Mbps from the UML instance of node A > to the host kernel of node B and 100 Mbps from the host kernel of node A to > the host kernel of node B. However, when we use UDP the throughput is only > 26 Mbps from the UML instance on node A to the host kernel of node B, but > 100 Mbps from the host kernel of node A to the host kernel of node B. We > also notice that a large number of packets were dropped in the case of UDP > over UML. At what interface are the packets being dropped? Jeff -- Work email - jdike at linux dot intel dot com ------------------------------------------------------------------------- This SF.net email is sponsored by DB2 Express Download DB2 Express C - the FREE version of DB2 express and take control of your XML. No limits. Just data. Click to get it now. http://sourceforge.net/powerbar/db2/ _______________________________________________ User-mode-linux-devel mailing list User-mode-linux-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/user-mode-linux-devel ------------------------------------------------------------------------- This SF.net email is sponsored by DB2 Express Download DB2 Express C - the FREE version of DB2 express and take control of your XML. No limits. Just data. Click to get it now. http://sourceforge.net/powerbar/db2/ _______________________________________________ User-mode-linux-devel mailing list User-mode-linux-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/user-mode-linux-devel From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from sc8-sf-mx1-b.sourceforge.net ([10.3.1.91] helo=mail.sourceforge.net) by sc8-sf-list1-new.sourceforge.net with esmtp (Exim 4.43) id 1HyHbJ-000704-IG for user-mode-linux-devel@lists.sourceforge.net; Tue, 12 Jun 2007 18:24:47 -0700 Received: from saraswathi.solana.com ([198.99.130.12]) by mail.sourceforge.net with esmtps (TLSv1:AES256-SHA:256) (Exim 4.44) id 1HyHbH-0005TP-Nl for user-mode-linux-devel@lists.sourceforge.net; Tue, 12 Jun 2007 18:24:45 -0700 Date: Tue, 12 Jun 2007 21:24:32 -0400 From: Jeff Dike Message-ID: <20070613012432.GA12102@c2.user-mode-linux.org> References: <010701c7ace0$f98b0d80$d8c8a8c0@angel4> <20070612150405.GA7102@c2.user-mode-linux.org> <036601c7ad52$4b0c76a0$d8c8a8c0@angel4> Mime-Version: 1.0 Content-Disposition: inline In-Reply-To: <036601c7ad52$4b0c76a0$d8c8a8c0@angel4> Subject: Re: [uml-devel] UDP vs. TCP performance over UML List-Id: The user-mode Linux development list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: user-mode-linux-devel-bounces@lists.sourceforge.net Errors-To: user-mode-linux-devel-bounces@lists.sourceforge.net To: George Hadjichristofi Cc: 'shruti singhal' , user-mode-linux-devel@lists.sourceforge.net On Tue, Jun 12, 2007 at 08:32:15PM -0400, George Hadjichristofi wrote: > In the case of A to B (with UML on A) there are packets dropped. Based on > Ifconfig on the host kernel the packets seem to drop between tap0 and eth0 > on the host kernel. (i.e., the number of packets on tap0 is higher than > eth0). ifconfig tells you directly how many packets are dropped. What does the "dropped:" field say? Jeff -- Work email - jdike at linux dot intel dot com ------------------------------------------------------------------------- This SF.net email is sponsored by DB2 Express Download DB2 Express C - the FREE version of DB2 express and take control of your XML. No limits. Just data. Click to get it now. http://sourceforge.net/powerbar/db2/ _______________________________________________ User-mode-linux-devel mailing list User-mode-linux-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/user-mode-linux-devel