From owner-freebsd-current@FreeBSD.ORG Tue Apr 27 05:08:37 2004 Return-Path: Delivered-To: freebsd-current@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 66C6816A4CE for ; Tue, 27 Apr 2004 05:08:37 -0700 (PDT) Received: from pinus.cc.fer.hr (pinus.cc.fer.hr [161.53.73.18]) by mx1.FreeBSD.org (Postfix) with ESMTP id ABF2E43D5F for ; Tue, 27 Apr 2004 05:08:36 -0700 (PDT) (envelope-from ivoras@fer.hr) Received: from fer.hr (lara.cc.fer.hr [161.53.72.113]) by pinus.cc.fer.hr (8.12.2/8.12.2) with ESMTP id i3RCAcsM006419; Tue, 27 Apr 2004 14:10:38 +0200 (MEST) Message-ID: <408E4C62.9090207@fer.hr> Date: Tue, 27 Apr 2004 14:04:50 +0200 From: Ivan Voras User-Agent: Mozilla Thunderbird 0.5 (Windows/20040207) X-Accept-Language: en-us, en MIME-Version: 1.0 To: Luigi Rizzo References: <408D85FD.10809@fer.hr> <20040426153919.A74609@xorpc.icir.org> <408DA87E.3000603@fer.hr> <20040427043253.B50266@xorpc.icir.org> In-Reply-To: <20040427043253.B50266@xorpc.icir.org> Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit cc: current@freebsd.org Subject: Re: Dummynet low bandwidth simulation X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 27 Apr 2004 12:08:37 -0000 Luigi Rizzo wrote: > considering your msg about rst etc -- there are a number of potential > failure modes including the most likely one below: > > + because of the extra delay, the initial syn handshake takes too > long to complete causing way too many entries in the listen queue, > so this saturates the server side. I dont' understand this - the messages ("limiting RST response freq.") are not showing on the server side (where the web server is), but on the client. (Apache's default backlog is 511 and I raised kern.ipc.somaxconn to 1000 on the server). But I've discovered a possible cause: apache httpd processes have been dyeing on the server, and occasionally I see: "collecting pv entries, suggest increasing PMAP_SHPGPERPROC". What is that? -- Every sufficiently advanced magic is indistinguishable from technology - Arthur C Anticlarke