From owner-freebsd-net@FreeBSD.ORG Thu Jan 30 15:12:08 2014 Return-Path: Delivered-To: freebsd-net@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [8.8.178.115]) (using TLSv1 with cipher ADH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTPS id D78A0BD2 for ; Thu, 30 Jan 2014 15:12:08 +0000 (UTC) Received: from mail-qa0-x22a.google.com (mail-qa0-x22a.google.com [IPv6:2607:f8b0:400d:c00::22a]) (using TLSv1 with cipher ECDHE-RSA-RC4-SHA (128/128 bits)) (No client certificate requested) by mx1.freebsd.org (Postfix) with ESMTPS id 96E8A15C3 for ; Thu, 30 Jan 2014 15:12:08 +0000 (UTC) Received: by mail-qa0-f42.google.com with SMTP id k4so4552913qaq.15 for ; Thu, 30 Jan 2014 07:12:07 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:sender:in-reply-to:references:date:message-id:subject :from:to:cc:content-type; bh=LwkMeLNNvlicyXbBmSJES5ymzZNGHsGZVAELUI5ZbtE=; b=rLrIHDuDA+2fYXb49F6FroYECzG53qs8lUq6eh2Uz3T8R7bxzLsr9TSZilj6PAntK9 mvlyxc1/l1osv9Cipqp3zhTLYkDwAvI7pMpOp902CZg48mGhDtTrMl/CPUQkLMq8SCdV alkMCs35KPfpkdcjVUenGNdWJeJzYXgTNMUHEYOcEzB1Z3cCHbov0Fx37N3dxRqHI+fh bEAAlsErEZAL6TR0EovDQxUhP/cdw861rdatMgVZMUGv8kkyZ9TAmHhGbiqZoWDPtIAM alMinID2+419OYZPiEBessyerTq939tjE0q15s69Kf8FLkrY6cVH9RB8uPOrGAchF+Uf UKjQ== MIME-Version: 1.0 X-Received: by 10.140.108.74 with SMTP id i68mr21004155qgf.87.1391094727736; Thu, 30 Jan 2014 07:12:07 -0800 (PST) Sender: adrian.chadd@gmail.com Received: by 10.224.52.8 with HTTP; Thu, 30 Jan 2014 07:12:07 -0800 (PST) In-Reply-To: <1217356349.106076.1391094388165.JavaMail.root@uoguelph.ca> References: <1217356349.106076.1391094388165.JavaMail.root@uoguelph.ca> Date: Thu, 30 Jan 2014 07:12:07 -0800 X-Google-Sender-Auth: lY59v5VrBUmI-QO7Ts9UvkRKGzo Message-ID: Subject: Re: 64K NFS I/O generates a 34mbuf list for TCP which breaks TSO From: Adrian Chadd To: Rick Macklem Content-Type: text/plain; charset=ISO-8859-1 Cc: FreeBSD Net X-BeenThere: freebsd-net@freebsd.org X-Mailman-Version: 2.1.17 Precedence: list List-Id: Networking and TCP/IP with FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 30 Jan 2014 15:12:08 -0000 On 30 January 2014 07:06, Rick Macklem wrote: > Hi, just adding one more idea on what to do about this > to the list: > - Add a if_hw_tsomaxseg and modify the loop in tcp_output() > so that it uses both if_hw_tsomax and if_hw_tsomaxseg to > decide how much to hand to the device driver in each mbuf list. > (I haven't looked to see how easy it would be to change this loop.) I don't think that's a hack. I think adding that and setting tsomaxseg to say 30 for now would be a good comprimise. -a