From owner-freebsd-net@FreeBSD.ORG Sat Apr 19 04:33:06 2008 Return-Path: Delivered-To: net@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 25FFC1065671 for ; Sat, 19 Apr 2008 04:33:06 +0000 (UTC) (envelope-from delphij@delphij.net) Received: from tarsier.delphij.net (delphij-pt.tunnel.tserv2.fmt.ipv6.he.net [IPv6:2001:470:1f03:2c9::2]) by mx1.freebsd.org (Postfix) with ESMTP id A60D08FC25 for ; Sat, 19 Apr 2008 04:33:04 +0000 (UTC) (envelope-from delphij@delphij.net) Received: from tarsier.geekcn.org (tarsier.geekcn.org [202.108.54.204]) (using TLSv1 with cipher ADH-CAMELLIA256-SHA (256/256 bits)) (No client certificate requested) by tarsier.delphij.net (Postfix) with ESMTPS id 6626228450 for ; Sat, 19 Apr 2008 12:32:58 +0800 (CST) Received: from localhost (tarsier.geekcn.org [202.108.54.204]) by tarsier.geekcn.org (Postfix) with ESMTP id 1B1BDEC6C7B; Sat, 19 Apr 2008 12:32:57 +0800 (CST) X-Virus-Scanned: amavisd-new at geekcn.org Received: from tarsier.geekcn.org ([202.108.54.204]) by localhost (mail.geekcn.org [202.108.54.204]) (amavisd-new, port 10024) with ESMTP id A06i5jmMKyHW; Sat, 19 Apr 2008 12:32:48 +0800 (CST) Received: from charlie.delphij.net (c-69-181-135-56.hsd1.ca.comcast.net [69.181.135.56]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by tarsier.geekcn.org (Postfix) with ESMTPSA id 65D0BEC6ADF; Sat, 19 Apr 2008 12:32:41 +0800 (CST) DomainKey-Signature: a=rsa-sha1; s=default; d=delphij.net; c=nofws; q=dns; h=message-id:date:from:reply-to:organization:user-agent: mime-version:to:cc:subject:references:in-reply-to: x-enigmail-version:openpgp:content-type:content-transfer-encoding; b=p5JI6ROYX5Mu+ubbm07gK3ZiJKgnOCxyA9eEb0mm9gi16LnEIG8HTohjFqc4/5GbP p2QuStw3QgjtoLpCY/eEw== Message-ID: <480975DC.3090600@delphij.net> Date: Fri, 18 Apr 2008 21:32:28 -0700 From: Xin LI Organization: The FreeBSD Project User-Agent: Thunderbird 2.0.0.12 (X11/20080312) MIME-Version: 1.0 To: "George V. Neville-Neil" References: <48087C98.8060600@delphij.net> <382258DB-13B8-4108-B8F4-157F247A7E4B@hughes.net> In-Reply-To: X-Enigmail-Version: 0.95.6 OpenPGP: id=18EDEBA0; url=http://www.delphij.net/delphij.asc Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: Chris Pratt , d@delphij.net, net@freebsd.org Subject: Re: zonelimit issues... X-BeenThere: freebsd-net@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list Reply-To: d@delphij.net List-Id: Networking and TCP/IP with FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 19 Apr 2008 04:33:06 -0000 George V. Neville-Neil wrote: [snip] > I believe that a better solution is possible, but it will take more > careful study. One option is to start adding drain routines to UDP > that cause the protocol to drop packets under load, which is the > problem we're seeing. In our tests the server process cannot read > data fast enough to clear enough mbufs/clusters back to the system and > it gets stuck in a write() call. I'm not very sure, but in the past, the problem seems to be that for some reasons the sleep threads on zonelim were not being awaken any more, have you tried to adjust the nmbcluster sysctl (like a 2x increase) to see if the problem goes away? Cheers, -- Xin LI http://www.delphij.net/ FreeBSD - The Power to Serve!