From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx6.haw-public.haw-hamburg.de ([141.22.6.3]:57507 "EHLO mx6.haw-public.haw-hamburg.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750993AbcDGU3t (ORCPT ); Thu, 7 Apr 2016 16:29:49 -0400 From: Peter Kietzmann Subject: UDP stress-testing Message-ID: <5706C0D7.1040000@haw-hamburg.de> Date: Thu, 7 Apr 2016 22:19:35 +0200 MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8"; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-wpan-owner@vger.kernel.org List-ID: To: linux-wpan@vger.kernel.org Dear list, first of all let me say that I'm new to this list. So if I'm completely wrong in my concern please excuse the noise and guide me to the right place. If you can :-)! For some experiments I'm trying to send "great" numbers of UDP packets with "great" payloads as fast as possible from a RasPi equipped with the Openlabs transceiver. With another RasPi+transceiver I'm sniffing the traffic. It turns out that just the first x packets are sent out correctly before the outgoing packets come out irregularly. The number of correctly sent packets depends on the UDP payload size and it looks like the problem occurs after ~30-35 kB Bytes (gross) in total have been transmitted (fragmentation overhead included). I already increased the send socket memory to a reasonably high value, without success. But still I assume some buffer problems. Do you have a hint which screw to adjust? BTW: Introducing a delay after each packet to send fixes the problem. But I'd like to do stress-testing... Best Peter -- Peter Kietzmann Hamburg University of Applied Sciences Dept. Informatik, Internet Technologies Group Berliner Tor 7, 20099 Hamburg, Germany Fon: +49-40-42875-8426 Web: http://www.haw-hamburg.de/inet