From owner-freebsd-questions@FreeBSD.ORG Thu Mar 22 09:47:43 2012 Return-Path: Delivered-To: freebsd-questions@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 64F01106566C for ; Thu, 22 Mar 2012 09:47:43 +0000 (UTC) (envelope-from freebsd-questions@herveybayaustralia.com.au) Received: from mail.unitedinsong.com.au (mail.unitedinsong.com.au [150.101.178.33]) by mx1.freebsd.org (Postfix) with ESMTP id 132DD8FC1F for ; Thu, 22 Mar 2012 09:47:42 +0000 (UTC) Received: from laptop1.herveybayaustralia.com.au (laptop1.herveybayaustralia.com.au [192.168.0.182]) (using TLSv1 with cipher DHE-RSA-CAMELLIA256-SHA (256/256 bits)) (No client certificate requested) by mail.unitedinsong.com.au (Postfix) with ESMTPSA id 9AFA65C22 for ; Thu, 22 Mar 2012 20:01:09 +1000 (EST) Message-ID: <4F6AF535.9010302@herveybayaustralia.com.au> Date: Thu, 22 Mar 2012 19:47:33 +1000 From: Da Rock User-Agent: Mozilla/5.0 (X11; FreeBSD amd64; rv:7.0.1) Gecko/20111109 Thunderbird/7.0.1 MIME-Version: 1.0 To: freebsd-questions@freebsd.org References: In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Subject: Re: FreeBSD: syslog-ng: I/O error occurred while writing; fd='xx', error='No buffer space available (yy)' X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 22 Mar 2012 09:47:43 -0000 On 03/22/12 19:00, Traiano Welcome wrote: > Hi List > > I've been seeing the following in the messages log of my freebsd syslog > server for quite some time now: > > --- > Mar 20 12:19:12 syslog2 syslog-ng[35313]: I/O error occurred while > writing; fd='12', error='No buffer space available (55)' > Mar 20 12:19:12 syslog2 syslog-ng[35313]: Connection broken; > time_reopen='60' > Mar 20 12:19:12 syslog2 syslog-ng[35313]: I/O error occurred while > writing; fd='13', error='No buffer space available (55)' > Mar 20 12:19:12 syslog2 syslog-ng[35313]: Connection broken; > time_reopen='60' > --- > > These happen at a frequency of about 7 per minute on average. See attached > trend graphs for an idea of the volume of traffic we're doing, as well as > the memory and cpu utilisation trends on this server during this period. > As can be seen from the graphs, load does not seem to be the issue. > Occasionally during the week, the system freezes and requires a reboot, I > think it's related to the above message, though I'm not sure. > > My question is: What does this error mean, and how can I resolve it? > > I have tried to frame this as an operating system kernel resource issue, > and experimented with increasing the freebsd kernel sysctls for UDP > performance: > > --- > [root@syslog2 /var/log]# > sysctl kern.ipc.nmbclusters=102400 > kern.ipc.nmbclusters: 25600 -> 102400 > > [root@syslog2 /var/log]# > sysctl kern.ipc.maxsockbuf=201326592 > kern.ipc.maxsockbuf: 100663296 -> 201326592 > > [root@syslog2 /var/log]# > sysctl net.inet.udp.recvspace=33554432 > net.inet.udp.recvspace: 16777216 -> 33554432 > --- > > This has reduced the frequency of the errors a little, but in general the > problem still remains. > > Syslog version: > > -- > [root@syslog2]# syslog-ng -V > syslog-ng 2.0.10 > > -- > > FreeBSD version: > > -- > FreeBSD 7.2-STABLE #0 > -- > > Any help would be much appreciated! I'm sorry I can't shed some light on a solution, but this happens on ping and some other network related apps and tools for me too; just not often enough for me concern with atm due to higher priorities. Perhaps net@ might be a better resource for an answer to this one?