From owner-freebsd-net@FreeBSD.ORG Tue Dec 27 16:43:17 2005 Return-Path: X-Original-To: freebsd-net@freebsd.org Delivered-To: freebsd-net@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 1D73016A41F for ; Tue, 27 Dec 2005 16:43:17 +0000 (GMT) (envelope-from skylar@cs.earlham.edu) Received: from quark.cs.earlham.edu (cs.earlham.edu [159.28.230.3]) by mx1.FreeBSD.org (Postfix) with ESMTP id C53D143D55 for ; Tue, 27 Dec 2005 16:43:15 +0000 (GMT) (envelope-from skylar@cs.earlham.edu) Received: from [192.168.0.11] (CPE-67-48-232-40.new.res.rr.com [67.48.232.40]) (authenticated bits=0) by quark.cs.earlham.edu (8.13.4/8.13.3) with ESMTP id jBRGg2Ii003118 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO); Tue, 27 Dec 2005 11:43:11 -0500 (EST) (envelope-from skylar@cs.earlham.edu) Message-ID: <43B16ED4.9060803@cs.earlham.edu> Date: Tue, 27 Dec 2005 10:41:56 -0600 From: Skylar Thompson Organization: Earlham College Computer Science Department User-Agent: Debian Thunderbird 1.0.7 (X11/20051017) X-Accept-Language: en-us, en MIME-Version: 1.0 To: Brian Candler References: <43B03332.2010904@cs.earlham.edu> <20051227130614.GA3148@uk.tiscali.com> In-Reply-To: <20051227130614.GA3148@uk.tiscali.com> X-Enigmail-Version: 0.93.0.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="------------enigC7C37149442DD4594104A43D" X-Greylist: Sender succeded SMTP AUTH authentication, not delayed by milter-greylist-1.6 (quark.cs.earlham.edu [159.28.230.3]); Tue, 27 Dec 2005 11:43:12 -0500 (EST) X-Virus-Scanned: ClamAV 0.87.1/1218/Mon Dec 26 08:46:59 2005 on quark.cs.earlham.edu X-Virus-Status: Clean X-Scanned-By: MIMEDefang 2.52 on 159.28.230.3 X-Spam-Status: No, score=0.1 required=8.0 tests=RCVD_IN_SORBS_DUL autolearn=no version=3.0.4 X-Spam-Checker-Version: SpamAssassin 3.0.4 (2005-06-05) on quark.cs.earlham.edu Cc: freebsd-net@freebsd.org Subject: Re: DHCP oddity X-BeenThere: freebsd-net@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list Reply-To: skylar@cs.earlham.edu List-Id: Networking and TCP/IP with FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 27 Dec 2005 16:43:17 -0000 This is an OpenPGP/MIME signed message (RFC 2440 and 3156) --------------enigC7C37149442DD4594104A43D Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Brian Candler wrote: >On Mon, Dec 26, 2005 at 12:15:14PM -0600, Skylar Thompson wrote: > > >>While doing some network stress-tests from a dual-CPU x86 FreeBSD 5.4 >>server, I noticed that a "ping -f" drives dhcpd's CPU usage way up. I >>put dhcpd into debug mode and didn't get any error messages. I then ran >>dhcpd with strace, and saw loads of these messages when I started the >>ping flood: >> >>select(8, [?], [?], [?], NULL) = 1 () >>gettimeofday({...}, NULL) = 0 >>recvfrom(4, 0xbfbfe090, 1500, 0, {...}, [?]) = 84 >>select(8, [?], [?], [?], NULL) = 1 () >>gettimeofday({...}, NULL) = 0 >>recvfrom(4, 0xbfbfe090, 1500, 0, {...}, [?]) = 84 >> >>Does anyone know why this would happen? >> >> > >Were you running tcpdump or similar at the same time, such that the >interface was put into promiscuous mode? > >Check using ifconfig that it is not (i.e. there is no PROMISC flag shown) >_______________________________________________ > > No. Here's the setup of the NIC: bge0: flags=8843 mtu 1500 options=1a inet 159.28.234.1 netmask 0xffffff00 broadcast 159.28.234.255 inet6 fe80::210:18ff:fe11:ea1f%bge0 prefixlen 64 scopeid 0x1 ether 00:10:18:11:ea:1f media: Ethernet autoselect (1000baseTX ) status: active I've also tried this using the on-board 100Mbps fxp adapter, and I get the same results. -- -- Skylar Thompson (skylar@cs.earlham.edu) -- http://www.cs.earlham.edu/~skylar/ --------------enigC7C37149442DD4594104A43D Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.2 (GNU/Linux) Comment: Using GnuPG with Thunderbird - http://enigmail.mozdev.org iD8DBQFDsW7Ysc4yyULgN4YRAsMhAJ9Sehsb3A1QSVR/K/wswzfQmB5q9gCcDbdm cMnFCcoyGUGYrWKLegEDXTY= =dPt/ -----END PGP SIGNATURE----- --------------enigC7C37149442DD4594104A43D--