From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: To: bluez-users@lists.sourceforge.net Subject: Re: [Bluez-users] Higher throughput with larger UDP packet size In-Reply-To: Message from Sean Loh of "Mon, 14 Feb 2005 03:47:07 PST." <20050214114707.9429.qmail@web41104.mail.yahoo.com> References: <20050214114707.9429.qmail@web41104.mail.yahoo.com> Message-ID: <14994.1108382316@csr.com> From: Peter Stephenson Sender: bluez-users-admin@lists.sourceforge.net Errors-To: bluez-users-admin@lists.sourceforge.net Reply-To: bluez-users@lists.sourceforge.net List-Unsubscribe: , List-Id: BlueZ users List-Post: List-Help: List-Subscribe: , List-Archive: Date: Mon, 14 Feb 2005 11:58:36 +0000 Sean Loh wrote: > I have established an IP network over the BlueZ stack > and have transmitted UDP packets at varying sizes. I > then assessed the throughput using the different > datagram packets sizes. Why is it that the larger UDP > packets obtain higher throughputs than the smaller UDP > packets (eg. 60,000 bytes vs 5000 bytes)? Shouldn't > the smaller UDP packets obtain an overall higher > througput since less time is spent for segmentation > and reassembly? CPU time is not an important factor; the big difference is the time to send packets over the air. The shorter packets have extra headers to encapsulate them at the lower levels, which makes all the difference. At the Bluetooth baseband level, by the way, 5000 bytes already counts as "large" and will have to be fragmented into quite a lot of packets transmitted over the air. However, I certainly don't recommend using smaller packets at the UDP level for the reason I've given. pws ********************************************************************** This email and any files transmitted with it are confidential and intended solely for the use of the individual or entity to whom they are addressed. If you have received this email in error please notify the system manager. ********************************************************************** ------------------------------------------------------- SF email is sponsored by - The IT Product Guide Read honest & candid reviews on hundreds of IT Products from real users. Discover which products truly live up to the hype. Start reading now. http://ads.osdn.com/?ad_id=6595&alloc_id=14396&op=click _______________________________________________ Bluez-users mailing list Bluez-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/bluez-users