From owner-freebsd-net@FreeBSD.ORG Wed Jul 6 21:45:56 2011 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 18857106566C for ; Wed, 6 Jul 2011 21:45:56 +0000 (UTC) (envelope-from davidch@broadcom.com) Received: from mms2.broadcom.com (mms2.broadcom.com [216.31.210.18]) by mx1.freebsd.org (Postfix) with ESMTP id A32658FC08 for ; Wed, 6 Jul 2011 21:45:55 +0000 (UTC) Received: from [10.9.200.131] by mms2.broadcom.com with ESMTP (Broadcom SMTP Relay (Email Firewall v6.3.2)); Wed, 06 Jul 2011 14:33:21 -0700 X-Server-Uuid: D3C04415-6FA8-4F2C-93C1-920E106A2031 Received: from IRVEXCHCCR01.corp.ad.broadcom.com ([10.252.49.30]) by IRVEXCHHUB01.corp.ad.broadcom.com ([10.9.200.131]) with mapi; Wed, 6 Jul 2011 14:28:37 -0700 From: "David Christensen" To: "pyunyh@gmail.com" , "Charles Sprickman" Date: Wed, 6 Jul 2011 14:28:19 -0700 Thread-Topic: bce packet loss Thread-Index: Acw8GaxfxFCHGfSjSemBIXP1BbFGjgABvtbg Message-ID: <5D267A3F22FD854F8F48B3D2B523819385C32D9115@IRVEXCHCCR01.corp.ad.broadcom.com> References: <20110706201509.GA5559@michelle.cdnetworks.com> In-Reply-To: <20110706201509.GA5559@michelle.cdnetworks.com> Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-cr-hashedpuzzle: FG5c Hi8J MKlk NMvS No35 QSxs QgPT UnG9 VJom ZzMJ Z3oH iUeo i0zn jwGf lnOB mKd4; 4; ZABhAHYAaQBkAGMAaABAAGYAcgBlAGUAYgBzAGQALgBvAHIAZwA7AGYAcgBlAGUAYgBzAGQALQBuAGUAdABAAGYAcgBlAGUAYgBzAGQALgBvAHIAZwA7AHAAeQB1AG4AeQBoAEAAZwBtAGEAaQBsAC4AYwBvAG0AOwBzAHAAbwByAGsAQABiAHcAYQB5AC4AbgBlAHQA; Sosha1_v1; 7; {C1215C4F-1ECB-49AA-8A0B-D5696DA98E5E}; ZABhAHYAaQBkAGMAaABAAGIAcgBvAGEAZABjAG8AbQAuAGMAbwBtAA==; Wed, 06 Jul 2011 21:28:19 GMT;UgBFADoAIABiAGMAZQAgAHAAYQBjAGsAZQB0ACAAbABvAHMAcwA= x-cr-puzzleid: {C1215C4F-1ECB-49AA-8A0B-D5696DA98E5E} acceptlanguage: en-US MIME-Version: 1.0 X-WSS-ID: 620A0B2B62O20343336-01-01 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: quoted-printable Cc: "freebsd-net@freebsd.org" , David Christensen Subject: RE: bce packet loss 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: Wed, 06 Jul 2011 21:45:56 -0000 > You had 282 RX buffer shortages and these frames were dropped. This > may explain why you see occasional packet loss. 'netstat -m' will > show which size of cluster allocation were failed. > However it seems you have 0 com_no_buffers which indicates > controller was able to receive all packets destined for this host. > You may host lost some packets(i.e. non-zero mbuf_alloc_failed_count) > but your controller and system was still responsive to the network > traffic. >=20 > Data sheet says IfHCInBadOctets indicates number of octets received > on the interface, including framing characters for packets that > were dropped in the MAC for any reason.=20 The IfHcInBadOctets counter says the controller received X bytes=20 that were bad on the wire (collisions, FCS errors, etc.). A value of 539,369 would equal about 355 frames @ 1518 bytes per frame. How bad that is really depends on the amount of time the server was running. The minimum bit-error rate (BER) for 1000Base-T is=20 10^-12, so running at line rate you'd expect to see an error very 1000 seconds according to the following link: http://de.brand-rex.com/LinkClick.aspx?fileticket=3DTFxnnLPedAg%3D&tabid=3D= 1956&mid=3D5686 Most vendors design to greater than 10^-12 and you're probably not running at line rate all the time so you should see fewer errors. In my testing I can go for days without seeing any errors, but if you run long enough or have marginal interconnects/cabling the=20 error rate will rise. Dave