From owner-freebsd-stable@FreeBSD.ORG Sun Nov 27 03:39:08 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 12B421065743; Sun, 27 Nov 2011 03:39:08 +0000 (UTC) (envelope-from lstewart@freebsd.org) Received: from lauren.room52.net (lauren.room52.net [210.50.193.198]) by mx1.freebsd.org (Postfix) with ESMTP id C97468FC18; Sun, 27 Nov 2011 03:39:07 +0000 (UTC) Received: from lstewart1.loshell.room52.net (ppp59-167-184-191.static.internode.on.net [59.167.184.191]) by lauren.room52.net (Postfix) with ESMTPSA id 67C747E824; Sun, 27 Nov 2011 14:39:06 +1100 (EST) Message-ID: <4ED1B0DA.2020209@freebsd.org> Date: Sun, 27 Nov 2011 14:39:06 +1100 From: Lawrence Stewart User-Agent: Mozilla/5.0 (X11; FreeBSD amd64; rv:7.0.1) Gecko/20111016 Thunderbird/7.0.1 MIME-Version: 1.0 To: Kris Bauer References: <4ECEF6FD.5050006@freebsd.org> <4ED077BF.10205@freebsd.org> In-Reply-To: <4ED077BF.10205@freebsd.org> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-Spam-Status: No, score=0.0 required=5.0 tests=UNPARSEABLE_RELAY autolearn=unavailable version=3.3.2 X-Spam-Checker-Version: SpamAssassin 3.3.2 (2011-06-06) on lauren.room52.net Cc: kerbzo@gmail.com, FreeBSD Release Engineering Team , stb@lassitu.de, raul@turing.b2n.org, george+freebsd@m5p.com, freebsd-stable@freebsd.org, freebsd@jdc.parodius.com 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: Sun, 27 Nov 2011 03:39:08 -0000 On 11/26/11 16:23, Lawrence Stewart wrote: > On 11/25/11 13:01, Lawrence Stewart wrote: >> On 11/24/11 18:02, Kris Bauer wrote: >>> Hello, >>> >>> I am currently experiencing an issue with FreeBSD 9.0-RC2 r227852 >>> where the >>> net.inet.tcp.reass.curesegments value is constantly increasing (and not >>> descreasing when there is nominal traffic with the box). It is causing >>> tcp >>> slowdowns as described with kern/155407: >>> >>> Exhausted net.inet.tcp.reass.maxsegments block recovering tcp session >>> (for >>> this socket and any other socket waiting for retransmited packets). >>> After >>> exhausted net.inet.tcp.reass.maxsegments allocation new entry in >>> tcp_reass >>> failed (for this socket and any other socket waiting for retransmited >>> packets). >>> >>> I have increased the reass.maxsegments value to 16384 to temporarily >>> avoid >>> the problem, but the cursegments number keeps rising and it seems it >>> will >>> occur again. >>> >>> Is this an issue that anyone else has seen? I can provide more >>> information >>> if need be. >> >> Thanks Kris, Raul and Stefan for the reports, I'll look into this. > > I think I've got it - a stupid 1 line logic bug. My apologies for > missing it when I reviewed the patch which introduced the bug (patch was > committed to head as r226113, MFCed to stable/9 as r226228). > > Due to some miscommunication, the initial patch was committed to and > MFCed from head much later than it should have been in the 9.0 release > cycle and instead of being included in the BETAs, didn't make it in > until 9.0-RC1 I believe i.e. only RC1 and RC2 should be experiencing the > issue. > > Could those who have reported the bug and are able to recompile their > kernel to test a patch please try the following and report back to the > list: > > http://people.freebsd.org/~lstewart/patches/misctcp/tcp_reass_plugzoneleak_10.x.r227986.patch > > > The patch is against head r227986 but will apply and work correctly for > 9.0 as well. Thanks to all for the reports and testing. I committed the patch to head (http://svn.freebsd.org/changeset/base/228016) and it will be MFCed to 9 soon pending feedback from the release engineering team. Cheers, Lawrence