From owner-cvs-src Thu Feb 27 11: 3:33 2003 Delivered-To: cvs-src@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id CC08637B401; Thu, 27 Feb 2003 11:03:26 -0800 (PST) Received: from mail.tcoip.com.br (erato.tco.net.br [200.220.254.10]) by mx1.FreeBSD.org (Postfix) with ESMTP id 5F50A43FDF; Thu, 27 Feb 2003 11:03:13 -0800 (PST) (envelope-from dcs@tcoip.com.br) Received: from tcoip.com.br ([10.0.2.6]) by mail.tcoip.com.br (8.11.6/8.11.6) with ESMTP id h1RJ3A920441; Thu, 27 Feb 2003 16:03:10 -0300 Message-ID: <3E5E60ED.70406@tcoip.com.br> Date: Thu, 27 Feb 2003 16:03:09 -0300 From: "Daniel C. Sobral" User-Agent: Mozilla/5.0 (X11; U; FreeBSD i386; en-US; rv:1.3b) Gecko/20030214 X-Accept-Language: en-us, en, pt-br, ja MIME-Version: 1.0 To: Bill Paul Cc: jlemon@FreeBSD.ORG, ru@FreeBSD.ORG, src-committers@FreeBSD.ORG, cvs-src@FreeBSD.ORG, cvs-all@FreeBSD.ORG Subject: Re: cvs commit: src/sys/dev/fxp if_fxp.c if_fxpreg.h if_fxpvar.h References: <20030227183346.657C937B401@hub.freebsd.org> In-Reply-To: <20030227183346.657C937B401@hub.freebsd.org> Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Sender: owner-cvs-src@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG Bill Paul wrote: > Er... look. The checksum offload capabilities are turned on by default, > if your chip supports them, which it appears it does. Also, please try > and remember just how bent I can get at someone who says "it doesn't > work" without defining in precise detail just what "it" is and what > "doesn't work" implies. > > Do you mean that using ifconfig to twiddle the capabilities doesn't > seem to make any difference? > Do you mean that the cards aren't working with the updated driver (i.e. > you can't talk to the network)? > Do you mean they work but you don't notice any significant performance > difference? > Do you mean the machine halts and catches fire? Well, whenever I use that txcsum/rxcsum thingy, the machine acquires a kind of life-like appearance, and sends some strange pulses through the TP cables and start gobbling all other switches it is connected to in a similar fashion, in a manner very much like the BOOMERs of BubbleGum Crisis and AD Police. I'm still wondering if that's an advanced feature added by the .jp crew or not, though. :-) What I mean by "doesn't work" was what I cut&pasted. If the messages didn't show it, sorry, I must have made a mistake when preparing them. I asked how I could see if the thing was in use or not. Someone told me to look in the "options" field displayed by ifconfig. Well: root@piratinga:/root# ifconfig fxp2 | grep options options=8 dcs@pajeus:/home/dcs$ ifconfig xl0 | grep options options=3 From where I concluded the option was not active. So I asked how I activated it, and was told to use the undocumented options rxcsum and txcsum. I did that and: root@piratinga:/root# ifconfig fxp2 rxcsum txcsum root@piratinga:/root# ifconfig fxp2 | grep options options=8 Nothing happened wrt to what ifconfig displayed. Now, someone, maybe on irc, also told me -m would show the available options. The result of this was: root@piratinga:/root# ifconfig -m fxp2 fxp2: flags=8843 mtu 1500 options=8 capability list: =b [...] So, -m in fact shows rxcsum and txcsum being supported capabilities, but they are never listed in options, no matter what I do. > Like I said, you don't have to do anything to use the checksum offload > capabilities: they're just on, and that's that. In terms of peformance, > the fact that the chip doesn't do checksums over fragmented packets > means that the biggest improvement will be with packets that fit into > a single frame. I suspect not even that, as all traffic going through these interfaces is 802.1q, and you mentioned IP checksum not being on for now. So, ignoring all that, my questions are: 1) How do I know if an interface has actually been identified as supporting the feature? 2) How do I know if the feature is in use? 3) If it can be turned on/off, how do I do it? 4) If the answer to any of these questions is the stuff I did above, why didn't it result in, well, the expected results? -- Daniel C. Sobral (8-DCS) Gerencia de Operacoes Divisao de Comunicacao de Dados Coordenacao de Seguranca TCO Fones: 55-61-313-7654/Cel: 55-61-9618-0904 E-mail: Daniel.Capo@tco.net.br Daniel.Sobral@tcoip.com.br dcs@tcoip.com.br Outros: dcs@newsguy.com dcs@freebsd.org capo@notorious.bsdconspiracy.net "Don't tell me I'm burning the candle at both ends -- tell me where to get more wax!!" To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe cvs-src" in the body of the message