From owner-freebsd-net@FreeBSD.ORG Wed Feb 26 17:56:24 2014 Return-Path: Delivered-To: freebsd-net@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) (using TLSv1 with cipher ADH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTPS id 563B0984 for ; Wed, 26 Feb 2014 17:56:24 +0000 (UTC) Received: from mail-qc0-x22d.google.com (mail-qc0-x22d.google.com [IPv6:2607:f8b0:400d:c01::22d]) (using TLSv1 with cipher ECDHE-RSA-RC4-SHA (128/128 bits)) (No client certificate requested) by mx1.freebsd.org (Postfix) with ESMTPS id 13E0E1595 for ; Wed, 26 Feb 2014 17:56:24 +0000 (UTC) Received: by mail-qc0-f173.google.com with SMTP id x3so1826487qcv.4 for ; Wed, 26 Feb 2014 09:56:23 -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=4lAB3bqPvfj+sjfdq1oeIFBGbhzEyAc6i8kbhDbYphE=; b=zlw8JDD3QkA0ShkUk4VXx1KZs2qwOGKiPEdr4WgpEsVq+eeXE55g1MXucAuGNpg8gP 6OBIGHGKVoYr+84JLmXC9CpttC9RgisXBxis3SuivO6CmEM6DjfBO9H3FEQbflOEj+ya OGaMSXup0+HSxQbn+Bk3EhcIiiAM6Y2WBOdnUFYCoVTBQuEazPZEwXYrkQ4qemE+epJQ kOE/j0HocD0PfEMovlr8Dma7O0LA9zvzOs5VeH6aElsL3a8OaAWNJFkuSwjtTDNeC9BC WBUYvZUjwVSOZ5RNqfdLHXegdrTDaXS3VCbf6dSSK2iDm87VQI/ZdGjvpCAgXYVZ9yfY DqXQ== MIME-Version: 1.0 X-Received: by 10.140.42.54 with SMTP id b51mr894996qga.87.1393437383221; Wed, 26 Feb 2014 09:56:23 -0800 (PST) Sender: adrian.chadd@gmail.com Received: by 10.224.16.10 with HTTP; Wed, 26 Feb 2014 09:56:23 -0800 (PST) In-Reply-To: References: Date: Wed, 26 Feb 2014 09:56:23 -0800 X-Google-Sender-Auth: kqW27yvTZb4GLpWUMeNBKPV_bA0 Message-ID: Subject: Re: TSO From: Adrian Chadd To: Sami Halabi 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: Wed, 26 Feb 2014 17:56:24 -0000 Hi, TSO is needed for high throughput TCP work. The cost of output packet handling (lookups, pcb locks) and the CPU use in tcp_output() is quite high. It'd be great to fix that though. :) -a On 26 February 2014 09:37, Sami Halabi wrote: > Hi, > I'm reading (almost) all mailing emails in mailig list... > > Almost every / many problem in network performancr / packets loss ended up > suggesting disabling TSO. > > I wonder why.. Is it a bug in the implementation? Or bybdesign? > What are the usecases that TSO is needed? Myabe it should be disabled bt > default? > > Thanks in advance, > Sami > _______________________________________________ > 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"