From owner-freebsd-net@FreeBSD.ORG Thu Apr 17 14:34:01 2008 Return-Path: Delivered-To: freebsd-net@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 0E9BB106564A for ; Thu, 17 Apr 2008 14:34:01 +0000 (UTC) (envelope-from chris@arnold.se) Received: from mailstore.infotropic.com (mailstore.infotropic.com [213.136.34.3]) by mx1.freebsd.org (Postfix) with ESMTP id 595658FC29 for ; Thu, 17 Apr 2008 14:34:00 +0000 (UTC) (envelope-from chris@arnold.se) Received: (qmail 94302 invoked by uid 89); 17 Apr 2008 14:07:18 -0000 Received: by simscan 1.2.0 ppid: 94297, pid: 94299, t: 0.1395s scanners: attach: 1.2.0 clamav: 0.90/m:42 Received: from unknown (HELO ?192.168.123.123?) (chris@arnold.se@212.71.168.45) by mailstore.infotropic.com with ESMTPA; 17 Apr 2008 14:07:18 -0000 Date: Thu, 17 Apr 2008 16:07:16 +0200 (CEST) From: Christopher Arnold X-X-Sender: chris@localhost To: Alexander Sack In-Reply-To: <3c0b01820804170643w6b771ce9jdfc2dc5b240922b@mail.gmail.com> Message-ID: <20080417160712.S5510@localhost> References: <3c0b01820804160929i76cc04fdy975929e2a04c0368@mail.gmail.com> <200804161456.20823.jkim@FreeBSD.org> <3c0b01820804161328m77704ca0g43077a9718d446d4@mail.gmail.com> <200804161654.22452.jkim@FreeBSD.org> <3c0b01820804161402u3aac4425n41172294ad33a667@mail.gmail.com> <20080417112329.G47027@delplex.bde.org> <3c0b01820804170643w6b771ce9jdfc2dc5b240922b@mail.gmail.com> X-message-flag: =?ISO-8859-1?Q?Outlook_isn=B4t_compliant_with_current_standards?= =?ISO-8859-1?Q?_please_install_another_mail_client!?= MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII; format=flowed Cc: freebsd-net@freebsd.org Subject: Re: bge dropping packets issue X-BeenThere: freebsd-net@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Networking and TCP/IP with FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 17 Apr 2008 14:34:01 -0000 On Thu, 17 Apr 2008, Alexander Sack wrote: > For my own edification, when do you want use DEVICE_POLLING versus > interrupt driven network I/O? With all question like these I suppose > the answer depends on the workload and the interrupt bandwidth of the > machine (which depends on the type of hardware)... > > But why was it added to begin with if standard interrupt driven I/O is > faster? (was it the fact that historically hardware didn't do > interrupt coalescing initially) > The ability to reserve cpu is one of the great features. If your host is being DDOS'ed it is good to have a portion of the CPU reserved to applications so a) the machine dosn't die. and b) so you can continue to login and investigate and perhaps solve the problem. /Chris -- http://www.arnold.se/ http://www.mbit.us/