From owner-freebsd-stable@FreeBSD.ORG Thu Nov 24 17:53:25 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 E12E2106564A for ; Thu, 24 Nov 2011 17:53:25 +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 A01958FC15 for ; Thu, 24 Nov 2011 17:53:25 +0000 (UTC) Received: by iakl21 with SMTP id l21so5040597iak.13 for ; Thu, 24 Nov 2011 09:53:25 -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=Y0Yl6YPTHSM2rPil5LRNUIe0Ou28MIwwlLWEzh5vOc8=; b=jiiXh5krjkBLDaTsydAABVHYFvWELCEubWJS2F6/iHjM2LvS9jYuUdM3JAdAWIEzXR i55sKrEcS6ovZkxFif22mX1RL8Eii2+KLaThSS2RlDpWHduMzvTFJ2zP/B8iyivHah/B Dg/E8YBBVqAuKlHeXbFlLdhT9M+6CsMmYrQBI= MIME-Version: 1.0 Received: by 10.42.162.130 with SMTP id y2mr7849267icx.26.1322157204439; Thu, 24 Nov 2011 09:53:24 -0800 (PST) Received: by 10.50.34.167 with HTTP; Thu, 24 Nov 2011 09:53:24 -0800 (PST) In-Reply-To: References: Date: Thu, 24 Nov 2011 11:53:24 -0600 Message-ID: From: Kris Bauer To: Ivan Voras Content-Type: text/plain; charset=ISO-8859-1 X-Content-Filtered-By: Mailman/MimeDel 2.1.5 Cc: freebsd-stable@freebsd.org 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: Thu, 24 Nov 2011 17:53:26 -0000 On Thu, Nov 24, 2011 at 10:33 AM, Ivan Voras wrote: > On 24.11.2011. 8:02, 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. >> > > Is your configuration different than the default in some way? Do you use a > firewall? Multithreaded netisr? One of the new TCP congestion control > modules? > > > _______________________________________________ > freebsd-stable@freebsd.org mailing list > http://lists.freebsd.org/mailman/listinfo/freebsd-stable > To unsubscribe, send any mail to "freebsd-stable-unsubscribe@freebsd.org" > I don't believe that my configuration is anything out of the usual. Just some standard LFN tuning. sysctl.conf net.inet.tcp.blackhole=2 net.inet.udp.blackhole=1 kern.geom.eli.threads=2 kern.ipc.maxsockbuf=16777216 net.inet.tcp.cc.algorithm=htcp net.inet.tcp.sendbuf_max=16777216 net.inet.tcp.recvbuf_max=16777216 net.inet.tcp.sendbuf_auto=1 net.inet.tcp.recvbuf_auto=1 net.inet.tcp.sendbuf_inc=262144 net.inet.tcp.recvbuf_inc=524288 net.inet.tcp.sendspace=1048576 net.inet.tcp.recvspace=1048576 net.inet.tcp.hostcache.expire=1 net.inet.tcp.delayed_ack=0 boot/loader.conf vm.kmem_size_max="5120M" vm.kmem_size="5120M" geom_mirror_load="YES" vfs.zfs.arc_max="4096M" vfs.zfs.prefetch_disable=1 vfs.zfs.txg.timeout="15" vfs.zfs.write_limit_override="268435456" kern.ipc.nmbclusters="65536" cc_htcp_load="YES" net.inet.tcp.reass.maxsegments=16384 With the exception of the CC H-TCP and Reass maxsegments tunables, this is exactly what I was use with 8.2 with no issues. I have also seen the issue crop up (although I hadn't yet identified the source) while booting the box entirely with defaults (including using NewReno). The box is a 2 x Xeon E5405 Supermicro X7DCX with 8gb of RAM. Thanks, Kris