From owner-freebsd-stable@FreeBSD.ORG Fri Nov 25 18:05:13 2011 Return-Path: Delivered-To: freebsd-stable@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 016E81065672 for ; Fri, 25 Nov 2011 18:05:13 +0000 (UTC) (envelope-from george+freebsd@m5p.com) Received: from mailhost.m5p.com (ip-3-2-0-2.r20.asbnva02.us.ce.gin.ntt.net [IPv6:2001:418:0:5000::16]) by mx1.freebsd.org (Postfix) with ESMTP id A71298FC0A for ; Fri, 25 Nov 2011 18:05:12 +0000 (UTC) Received: from scollay.m5p.com (ssh.m5p.com [IPv6:2001:418:3fd::fb]) by mailhost.m5p.com (8.14.4/8.14.4) with ESMTP id pAPI56lQ080449 for ; Fri, 25 Nov 2011 13:05:11 -0500 (EST) (envelope-from george+freebsd@m5p.com) Message-ID: <4ECFD8D2.4030604@m5p.com> Date: Fri, 25 Nov 2011 13:05:06 -0500 From: George Mitchell User-Agent: Mozilla/5.0 (X11; FreeBSD amd64; rv:7.0.1) Gecko/20111111 Thunderbird/7.0.1 MIME-Version: 1.0 To: freebsd-stable@freebsd.org References: <4ECE9914.6020502@turing.b2n.org> <1A5B3A48-7DF3-4018-A244-152BDE96299A@lassitu.de> <20111125020004.GA36109@icarus.home.lan> In-Reply-To: <20111125020004.GA36109@icarus.home.lan> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-Greylist: Sender passed SPF test, not delayed by milter-greylist-4.2.7 (mailhost.m5p.com [IPv6:2001:418:3fd::f7]); Fri, 25 Nov 2011 13:05:11 -0500 (EST) X-Scanned-By: MIMEDefang 2.72 on IPv6:2001:418:3fd::f7 Subject: Re: TCP Reassembly Issues X-BeenThere: freebsd-stable@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Production branch of FreeBSD source code List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 25 Nov 2011 18:05:13 -0000 On 11/24/11 21:00, Jeremy Chadwick wrote: >[...] > If none of this solves the problem, then I consider this a priority 0 > blocker (read: "all hands on deck") issue with the IP stack in FreeBSD > 9.x and will need immediate attention. > > I would strongly recommend a developer or clueful end-user begin > tracking down who committed all of these bits and CC them into the > thread. I would start by looking who implemented the > net.inet.tcp.reass.cursegments sysctl, because that isn't in RELENG_8 at > all. > I've tried out the 9.0 release candidates, and what I notice is that for a few minutes after the system starts, I get wonderful NFS read throughput (7+ MB/s over a 100 megabit interface) -- more than twice as fast as 7.n or 8.n on the same hardware -- quickly degrading to abysmal (less than 0.5 MB/s). Is this possibly related to the problem under discussion? -- George Mitchell P.S. A lot of other 9.0 features look very nice indeed!