From owner-freebsd-stable@FreeBSD.ORG Sat Nov 26 06:49:25 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 AF9EE106564A; Sat, 26 Nov 2011 06:49:25 +0000 (UTC) (envelope-from kristoph.bauer@gmail.com) Received: from mail-iy0-f182.google.com (mail-iy0-f182.google.com [209.85.210.182]) by mx1.freebsd.org (Postfix) with ESMTP id 6B6448FC0C; Sat, 26 Nov 2011 06:49:25 +0000 (UTC) Received: by iakl21 with SMTP id l21so8612013iak.13 for ; Fri, 25 Nov 2011 22:49:24 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type; bh=kI8rp8TF7+VaYUoNPiiRaFtum3aApX1vhCiNi9/CHaI=; b=d6xaxTH1HIzUea7RYxrcbT1aTTHODnwzRRbaYejefw+To/AdMospX1EBDmz3x/g2Tm RYqt/edDAvmM9GssydI7SzrtO423JBgqsJ0Bqmr0DcT9zF3j4k/1AXekhD85zxF6DnbV CjIUHxYzm8nnxpTRVm5sC4nEXqs8xeCs9ROVk= MIME-Version: 1.0 Received: by 10.43.46.1 with SMTP id um1mr16049440icb.18.1322290164750; Fri, 25 Nov 2011 22:49:24 -0800 (PST) Received: by 10.50.34.167 with HTTP; Fri, 25 Nov 2011 22:49:24 -0800 (PST) In-Reply-To: <4ED077BF.10205@freebsd.org> References: <4ECEF6FD.5050006@freebsd.org> <4ED077BF.10205@freebsd.org> Date: Sat, 26 Nov 2011 00:49:24 -0600 Message-ID: From: Kris Bauer To: Lawrence Stewart Content-Type: text/plain; charset=ISO-8859-1 X-Content-Filtered-By: Mailman/MimeDel 2.1.5 Cc: kerbzo@gmail.com, freebsd-stable@freebsd.org, stb@lassitu.de, raul@turing.b2n.org, george+freebsd@m5p.com, FreeBSD Release Engineering Team , 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: Sat, 26 Nov 2011 06:49:25 -0000 On Fri, Nov 25, 2011 at 11:23 PM, 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. > > Cheers, > Lawrence > I have patched, recompiled, and rebooted. net.inet.tcp.reass.cursegments is no longer incrementing, and connectivity is holding steady. If anything changes over the next couple of hours, I'll be sure to report it; but all preliminary signs of the problem are gone. Thanks for all the help! Kris