From mboxrd@z Thu Jan 1 00:00:00 1970 Received: with ECARTIS (v1.0.0; list linux-mips); Sat, 07 Jan 2006 07:35:49 +0000 (GMT) Received: from dragonboat.cs.uoguelph.ca ([131.104.96.108]:39624 "EHLO dragonboat.cs.uoguelph.ca") by ftp.linux-mips.org with ESMTP id S8126484AbWAGHf2 (ORCPT ); Sat, 7 Jan 2006 07:35:28 +0000 Received: from beddie.cis.uoguelph.ca (marvin.cis.uoguelph.ca [131.104.48.131]) by dragonboat.cs.uoguelph.ca (8.13.1/8.13.1) with ESMTP id k077cDWd021183; Sat, 7 Jan 2006 02:38:13 -0500 Received: from localhost (localhost.localdomain [127.0.0.1]) by beddie.cis.uoguelph.ca (Postfix) with ESMTP id 53BA17E8F; Sat, 7 Jan 2006 02:36:17 -0500 (EST) Received: from beddie.cis.uoguelph.ca ([127.0.0.1]) by localhost (beddie [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 21768-06; Sat, 7 Jan 2006 02:36:16 -0500 (EST) Received: from [192.168.0.104] (CPE001217cc2ab6-CM001371143eca.cpe.net.cable.rogers.com [70.30.137.118]) by beddie.cis.uoguelph.ca (Postfix) with ESMTP id 685557D0D; Sat, 7 Jan 2006 02:36:16 -0500 (EST) Message-ID: <43BF6FE3.7030600@uoguelph.ca> Date: Sat, 07 Jan 2006 02:38:11 -0500 From: Brett Foster User-Agent: Mozilla Thunderbird 1.0 (Windows/20041206) X-Accept-Language: en-us, en MIME-Version: 1.0 To: kernel coder CC: linux-mips@linux-mips.org Subject: Re: Almost 80% of UDP packets dropped References: In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-Virus-Scanned: by amavisd-new-20030616-p10 (Debian) at cs-club.org X-Scanned-By: MIMEDefang 2.52 on 131.104.96.108 Return-Path: X-Envelope-To: <"|/home/ecartis/ecartis -s linux-mips"> (uid 0) X-Orcpt: rfc822;linux-mips@linux-mips.org Original-Recipient: rfc822;linux-mips@linux-mips.org X-archive-position: 9799 X-ecartis-version: Ecartis v1.0.0 Sender: linux-mips-bounce@linux-mips.org Errors-to: linux-mips-bounce@linux-mips.org X-original-sender: fosterb@uoguelph.ca Precedence: bulk X-list: linux-mips kernel coder wrote: >hi, > I was trying to measure the UDP reception speed on my borad which >has MIPS 4kc processor with 133 MHZ speed.I was transfering 10mb file >from intel pentium 4 machine to MIPS board,but the recieved file was >only 900kB. > > UDP was not designed with reliability in mind -- it really isn't meant for sending a 10 meg file without a packet loss. >When i further investigated the problem ,i came to know that the user >application was not getting enough opportunities to get data from >socket queue which caused almost 80% of packets to be dropped as >socket queue had no free space. > > (Among other sources) I'm pretty sure this behaviour was discussed in: Unix Network Programming, Vol. 1: The Sockets Networking API, Third Edition (Something like page 257.) I don't know if there is anything else going on with the kernel but... Brett