From owner-freebsd-net@FreeBSD.ORG Wed Mar 30 22:01:12 2011 Return-Path: Delivered-To: freebsd-net@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 52BEB106566B for ; Wed, 30 Mar 2011 22:01:12 +0000 (UTC) (envelope-from mike@jellydonut.org) Received: from mail-ew0-f54.google.com (mail-ew0-f54.google.com [209.85.215.54]) by mx1.freebsd.org (Postfix) with ESMTP id E65178FC17 for ; Wed, 30 Mar 2011 22:01:11 +0000 (UTC) Received: by ewy1 with SMTP id 1so608797ewy.13 for ; Wed, 30 Mar 2011 15:01:10 -0700 (PDT) MIME-Version: 1.0 Received: by 10.213.21.134 with SMTP id j6mr1200129ebb.141.1301520778254; Wed, 30 Mar 2011 14:32:58 -0700 (PDT) Received: by 10.213.105.204 with HTTP; Wed, 30 Mar 2011 14:32:58 -0700 (PDT) In-Reply-To: References: Date: Wed, 30 Mar 2011 17:32:58 -0400 Message-ID: From: Michael Proto To: Kyungsoo Lee Content-Type: text/plain; charset=ISO-8859-1 Cc: freebsd-net Subject: Re: UDP on FreeBSD X-BeenThere: freebsd-net@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Networking and TCP/IP with FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 30 Mar 2011 22:01:12 -0000 On Wed, Mar 30, 2011 at 3:43 PM, Kyungsoo Lee wrote: > Hi All, > > I want to check UDP on FreeBSD. > > I am using IPERF on FreeBSD for wireless testing with Proxim 8470 FC PCMCIA > card on IBM T42 and T61. > > When I'm transmitting data from FreeBSD to FreeBSD or CentOS using Iperf > with -u -b 100M on iperf, they had lost lots of packets. Sniffer near the > two nodes shows the sender could not send all packets. Iperf sender said > that they try to send 85469 packets but they lost 68824 packets. I think > that the UDP buffer on the sender could not handle all packets. > > But if I'm trying to send data from CentOS to FreeBSD using Iperf with -u -b > 100M option on iperf, the sender tries 18636 packets so they lost few > packets like 1 or 2 packets.As a result, they have similar bandwidth result > on the report. I think that it happens from different implement between > FreeBSD and Linux. > > But I want to double check that this is normal for FreeBSD or not. If I have > some missing points, let me know please. > > Thank you! > _______________________________________________ > freebsd-net@freebsd.org mailing list > http://lists.freebsd.org/mailman/listinfo/freebsd-net > To unsubscribe, send any mail to "freebsd-net-unsubscribe@freebsd.org" > Just a guess, but have you tried adjusting the net.inet.udp.maxdgram sysctl? I believe the default is somewhat low for UDP transmit. I don't know what size packets iperf is using but increasing the maxdgram value might help your testing. -Proto