Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1750766AbWEDSFO (ORCPT ); Thu, 4 May 2006 14:05:14 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751506AbWEDSFO (ORCPT ); Thu, 4 May 2006 14:05:14 -0400 Received: from bay105-f39.bay105.hotmail.com ([65.54.224.49]:61906 "EHLO hotmail.com") by vger.kernel.org with ESMTP id S1750766AbWEDSFN (ORCPT ); Thu, 4 May 2006 14:05:13 -0400 Message-ID: X-Originating-IP: [80.100.253.167] X-Originating-Email: [rwm_rietveld@hotmail.com] In-Reply-To: From: "Roy Rietveld" To: linux-kernel@vger.kernel.org Cc: linux-os@analogic.com, jengelh@linux01.gwdg.de Subject: Re: TCP/IP send, sendfile, RAW Date: Thu, 04 May 2006 18:05:09 +0000 Mime-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1; format=flowed X-OriginalArrivalTime: 04 May 2006 18:05:12.0511 (UTC) FILETIME=[49CD34F0:01C66FA5] Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3111 Lines: 76 Yes it is 100 MBits and there is a listener. and there are no other pc's on the link because its cross cable link. And when sending large buffers 32Kbyte it will do 80 MBits. It think that there is a lot of overhead in the fucntion send or something. >From: "linux-os (Dick Johnson)" >Reply-To: "linux-os (Dick Johnson)" >To: "Jan Engelhardt" >CC: "Roy Rietveld" >, >Subject: Re: TCP/IP send, sendfile, RAW >Date: Thu, 4 May 2006 13:56:31 -0400 > > >On Thu, 4 May 2006, Jan Engelhardt wrote: > > >> I would like to send ethernet packets with 1400 bytes payload. > >> I wrote a small program witch sends a buffer of 1400 bytes in a endless >loop. > >> The problem is that a would like 100Mbits throughtput but when i check >this > >> with ethereal. > >> I only get 40 MBits. I tried sending with an UDP socket and RAW socket. >I also > >> tried sendfile. > >> The RAW socket gives the best result till now 50 MBits throughtput. > > > > Limitation of Ethernet. > > > > > > > > Jan Engelhardt > >Maybe he can tell what he means by 100 MBits! If he is looking for >100 megabits per second, that's easy, That's 100/8 = 12.5 megabytes >per second. Anything, including Windows on a wet string, will >do that. If he is looking for 100 megabytes per second, that's >hard. He would need 100 * 8 = 800 megabits/second. A "gigabit" link >runs that fast if nobody else is on it, but there is a header and CRC >tail, in addition to the payload. UDP is the protocol to use to realize >this kind of bandwidth, but its possible for some packets to get lost and, >if they are routed, they could even be duplicated. Also, when testing >UDP, there must be a listener in order to realize the high speed. >You can't just spew out a dead-end link. > >Cheers, >Dick Johnson >Penguin : Linux version 2.6.16.4 on an i686 machine (5592.89 BogoMips). >New book: http://www.lymanschool.com >_ > > >**************************************************************** >The information transmitted in this message is confidential and may be >privileged. Any review, retransmission, dissemination, or other use of >this information by persons or entities other than the intended recipient >is prohibited. If you are not the intended recipient, please notify >Analogic Corporation immediately - by replying to this message or by >sending an email to DeliveryErrors@analogic.com - and destroy all copies of >this information, including any attachments, without reading or disclosing >them. > >Thank you. >- >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/ - 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/