From owner-freebsd-bugs@FreeBSD.ORG Fri Jan 13 18:22:00 2012 Return-Path: Delivered-To: freebsd-bugs@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id EC08A106566C for ; Fri, 13 Jan 2012 18:22:00 +0000 (UTC) (envelope-from jfvogel@gmail.com) Received: from mail-wi0-f182.google.com (mail-wi0-f182.google.com [209.85.212.182]) by mx1.freebsd.org (Postfix) with ESMTP id 7E25B8FC0A for ; Fri, 13 Jan 2012 18:22:00 +0000 (UTC) Received: by wibhm4 with SMTP id hm4so861715wib.13 for ; Fri, 13 Jan 2012 10:21:59 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type; bh=Z0VOLAyKBCKUIBWh3cZMWVcZ/0Zghupb9DfFqUXhrig=; b=mD+VnL7KFyDkdsbQhZrDNnnaiO5y+s7UWxYkHfFysepnf9P49bM929JPQZbncYoaAx ZVuW2pbQGvMqC6v2xjvqk/2nIs88r6vJjVUwXxQsPsuuCrt/jHd9xfrX3jAZVMX2erK4 YHmQ+YTfmfuJNNKjj16DNYhj9kye/zfdewzLs= MIME-Version: 1.0 Received: by 10.181.11.163 with SMTP id ej3mr3939747wid.4.1326477608700; Fri, 13 Jan 2012 10:00:08 -0800 (PST) Received: by 10.180.84.66 with HTTP; Fri, 13 Jan 2012 10:00:08 -0800 (PST) In-Reply-To: References: <4F106861.80507@cdf.toronto.edu> Date: Fri, 13 Jan 2012 10:00:08 -0800 Message-ID: From: Jack Vogel To: Iordan Iordanov Content-Type: text/plain; charset=ISO-8859-1 X-Content-Filtered-By: Mailman/MimeDel 2.1.5 Cc: freebsd-bugs@freebsd.org, CDF Admin Subject: Re: unable to set mtu 9000 on Intel x520-t2 adapter X-BeenThere: freebsd-bugs@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Bug reports List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 13 Jan 2012 18:22:01 -0000 Opps, i meant kern.ipc.nmb* of course... Jack On Fri, Jan 13, 2012 at 9:58 AM, Jack Vogel wrote: > Its a system resource thing, when you increase to a 9K mtu the driver will > use 9K > mbuf clusters, and with the queues and rings you have its unable to get > enough. > > Very important to look at kern.ipc.nbm* > > In your case nmbjumbo9 is the pool, if you had 4K it would those clusters. > Change the defaults in /etc/sysctl.conf. > > Cheers, > > Jack > > > > On Fri, Jan 13, 2012 at 9:22 AM, Iordan Iordanov wrote: > >> Hello, >> >> We are testing FreeBSD 9.0-RELEASE on a pair of machines with 10GBASE-T >> Intel x520-t2 adapters interconnected with a straight-through cat6 rj45 >> cable. With mtu 1500, we are achieving aproximately 4 gigabits/s both >> directions as demonstrated with iperf. We wanted to test with mtu 9000 to >> see whether there would be any difference, but we encountered a problem >> setting it. We ran the following commands to alter the MTU to 9000 on the >> two machines (fw3 and fw4): >> >> fw3# ifconfig ix1 192.168.1.100 mtu 9000 >> fw4# ifconfig ix1 192.168.1.200 mtu 9000 >> >> However, instead of getting mtu set to 9000, what we see is the following >> message in the kernel output of both machines: >> >> ix1: Could not setup receive structures >> ix1: Could not setup receive structures >> >> and no traffic getting through. The moment we run: >> >> fw3# ifconfig ix1 192.168.1.100 mtu 1500 >> fw4# ifconfig ix1 192.168.1.200 mtu 1500 >> >> we see: >> >> ix1: link state changed to DOWN >> ix1: link state changed to UP >> >> and traffic starts getting through as before. More information about our >> hardware is: >> >> Motherboard: Supermicro H8DGU-F >> CPU: AMD 6128 8-core >> Memory: 16GB DDR3 >> NICs: Intel x520-t2 10GbaseT adapters >> >> An ifconfig ix1 output for one of the machines: >> >> fw4# ifconfig ix1 >> ix1: flags=8843 metric 0 mtu >> 1500 >> >> options=401bb> MTU,VLAN_HWCSUM,TSO4,VLAN_**HWTSO> >> ether 00:1b:21:d6:19:51 >> inet 192.168.1.200 netmask 0xffffff00 broadcast 192.168.1.255 >> nd6 options=29 >> media: Ethernet autoselect (autoselect ) >> status: active >> >> >> Many thanks for any help/action on this! >> >> Sincerely, >> >> Iordan Iordanov >> CDF System Administrator >> University of Toronto >> ______________________________**_________________ >> freebsd-bugs@freebsd.org mailing list >> http://lists.freebsd.org/**mailman/listinfo/freebsd-bugs >> To unsubscribe, send any mail to "freebsd-bugs-unsubscribe@**freebsd.org >> " >> > >