From owner-freebsd-net@FreeBSD.ORG Wed Feb 26 23:28:51 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 27D8996D for ; Wed, 26 Feb 2014 23:28:51 +0000 (UTC) Received: from nm10-vm5.bullet.mail.ne1.yahoo.com (nm10-vm5.bullet.mail.ne1.yahoo.com [98.138.91.232]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.freebsd.org (Postfix) with ESMTPS id 9FE9218A1 for ; Wed, 26 Feb 2014 23:28:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=yahoo.com; s=gcom1024; t=1393457323; bh=YzZXBD/2V3W2yucHIvgfrY3sx1p6JjZR2JmJfilXWw8=; h=Received:Received:Received:DKIM-Signature:X-Yahoo-Newman-Id:X-Yahoo-Newman-Property:X-YMail-OSG:X-Yahoo-SMTP:X-Rocket-Received:Content-Type:Mime-Version:Subject:From:In-Reply-To:Date:Cc:Content-Transfer-Encoding:Message-Id:References:To:X-Mailer; b=RyWW6aUXx8UWtlyhZl3+WmIUza5OO3HM/CdfJ2hIPEaJDWWZIuZpAbjSrm9P2GKnanS6LTT5p05qqJ/CvzXXneVuE/uvSBOxCi3X23oNCPtQVxMTngh6mr4qrE5a2Shz/CAsoLYFouRvN+2ozCTVZClKz+ZuyaAXjEC54dpyQ8o= DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=gcom1024; d=yahoo.com; b=VTm31CkrnCE8EpsINHsT8fIQUGxuGPt66w+Zm9rKlMh1qV6nvnz5EbLHdMGEgzXD3Z9rZip3TBcNVubGJBbHRr1EDEzpYscxBsvet2J+8h6HDmxp0nQXCMLzQTuiAzmASXigCSMcyWRDDL8laM0Me2lzON4m5xc9FWpFnKvklkE=; Received: from [98.138.101.132] by nm10.bullet.mail.ne1.yahoo.com with NNFMP; 26 Feb 2014 23:28:43 -0000 Received: from [98.138.84.38] by tm20.bullet.mail.ne1.yahoo.com with NNFMP; 26 Feb 2014 23:28:43 -0000 Received: from [127.0.0.1] by smtp106.mail.ne1.yahoo.com with NNFMP; 26 Feb 2014 23:28:43 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=yahoo.com; s=s1024; t=1393457323; bh=YzZXBD/2V3W2yucHIvgfrY3sx1p6JjZR2JmJfilXWw8=; h=X-Yahoo-Newman-Id:X-Yahoo-Newman-Property:X-YMail-OSG:X-Yahoo-SMTP:X-Rocket-Received:Content-Type:Mime-Version:Subject:From:In-Reply-To:Date:Cc:Content-Transfer-Encoding:Message-Id:References:To:X-Mailer; b=peSUt+m66yaoRM7+PpV8DKazi6gBeqnEUA3WsvidLUGM3kxBIfkzRprjfuikYRgv0TkcCbgfXqcI2MlyOu1Kfuv6yiPmzQJBYnqdQ3R7evEFsZZNbVeKVPZMWVJmcYupwQTyQWrt4z35sXP3kUey11J9XqSscGgIsPjq4eCUkPM= X-Yahoo-Newman-Id: 352002.30008.bm@smtp106.mail.ne1.yahoo.com X-Yahoo-Newman-Property: ymail-3 X-YMail-OSG: kGJrw4cVM1lOx7T.eMASgxOLqC9z6dhZWC67QInJQYoEOyp KMa3wfU4C8pR9VGIRzOyOnxFbXpXsSRudDXsVkhaYRnnMQWdfPfsUVCZiR.Z _2YBa6XghGIh4TFewj2NnOOuW3szazqBFCKtIaoMHmXGLCiwla5zWT1mk2ak AWGGdmpJ9UoiOitiVsZlXjgXHbeCKkoO76wzLvR3SNN3Sy0i14x1uEWYtFJr CZ7Ljn4X5mMLxZH6yn6YMcd0DDVxUQ25PY_NXcxfM0NMymMKwdd9KUk6PqHL VcfPZhNWEcqCzuzBeWPDvZNQoZKGb_95XbfUqmqt0RIF0xCZmQciyWF.RoKM 8blAbYEArZJeFzqVDmnKQLXZ8lrib.F.hgze3mzitJ6njln98O.G2RLHXQzP QKJjitFlYhrAGP.SVhoMm0oqEG8AxgasCb_fRtx9BTM79iL3Iv2ANvZXxnvP k0F7Zw8rbQGiFhnQCdrNAlzntnZtYFvGUTZRXw.9bwukL3Rcgo4DIps8JB2S rNvHLifjhdIF9X1y2YZFMTWZf1ulMUJNBRNnfwOkZy4LrEyb76o89exIZVVW YG5DtYKZ9DEDMAg-- X-Yahoo-SMTP: clhABp.swBB7fs.LwIJpv3jkWgo2NU8- X-Rocket-Received: from lgmac-bvermilion.corp.netflix.com (scott4long@69.53.236.251 with plain [98.139.211.125]) by smtp106.mail.ne1.yahoo.com with SMTP; 26 Feb 2014 15:28:43 -0800 PST Content-Type: text/plain; charset=windows-1252 Mime-Version: 1.0 (Mac OS X Mail 7.1 \(1827\)) Subject: Re: TSO From: Scott Long In-Reply-To: <530E3211.6020805@vangyzen.net> Date: Wed, 26 Feb 2014 15:28:37 -0800 Content-Transfer-Encoding: quoted-printable Message-Id: <3F5216B4-2434-45BF-B83C-1D4E1643EAF6@yahoo.com> References: <530E3211.6020805@vangyzen.net> To: Eric van Gyzen X-Mailer: Apple Mail (2.1827) Cc: FreeBSD Net , Sami Halabi 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 23:28:51 -0000 On Feb 26, 2014, at 10:27 AM, Eric van Gyzen wrote: > On 02/26/2014 11:37, Sami Halabi wrote: >> Hi, >> I'm reading (almost) all mailing emails in mailig list... >>=20 >> Almost every / many problem in network performancr / packets loss = ended up >> suggesting disabling TSO. >>=20 >> 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? >=20 > In some cases, I have disabled TSO to [successfully] work around a bug > in a particular NIC's firmware or hardware, usually a low-end = "desktop" > gigabit NIC. >=20 The same thing happened 10-15 years ago with TCP Checksum offload. = Hardware support appeared, software support appeared, problems cropped up in = both, and it became an iterative process of identifying, disabling, and fixing. = It=92s now a solid feature that works without question (though there was a paper recently = claiming that hardware CSUM offload doesn=92t matter anymore for performance; = that=92s a different topic of discussion). Scott