From owner-svn-src-all@freebsd.org Fri Jan 5 17:38:42 2018 Return-Path: Delivered-To: svn-src-all@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id 7E26BEB60E4 for ; Fri, 5 Jan 2018 17:38:42 +0000 (UTC) (envelope-from steven@multiplay.co.uk) Received: from mail-wm0-x231.google.com (mail-wm0-x231.google.com [IPv6:2a00:1450:400c:c09::231]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (Client CN "smtp.gmail.com", Issuer "Google Internet Authority G2" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 0A58A74513 for ; Fri, 5 Jan 2018 17:38:42 +0000 (UTC) (envelope-from steven@multiplay.co.uk) Received: by mail-wm0-x231.google.com with SMTP id a79so3799271wma.0 for ; Fri, 05 Jan 2018 09:38:41 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=multiplay-co-uk.20150623.gappssmtp.com; s=20150623; h=subject:to:references:from:message-id:date:user-agent:mime-version :in-reply-to:content-language; bh=mXbSfU4JzPIfZQXL8I5iOBEBkj6jpQiQaU5i2UzkFxs=; b=FaG5up3FDmmH0/bvA6lMkH8g4M8KbSaIbAiPFkdum4G1GFZe3zhC4DF6HtnbTpPgzB /pdCqajpr82NJdQgDHUu0V7QL1bOdRNCIiEKmjgJOfdtAi+yUA8fb9tCI1X2Ke+G2yZJ 3BxyZGYDwHmK678X9cgDG7kj81/ujBYXovXCckPV8Z9l0fuZ/C5jX1Q28iRn/J6M6wJw JFQuZUSVbAW3gUEY+vwyfdjGZLxLdTRoy2JH/LiLlJ/Hfgtn/pj+S7ViKQ1OIc87++x3 v7MAgPTZMP+gSE78wH7hYSarufSsshJLP/MZutufA/GTbDqIwfXkPWyBHskgHKVTRQFe Qq7Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-language; bh=mXbSfU4JzPIfZQXL8I5iOBEBkj6jpQiQaU5i2UzkFxs=; b=RhdAtOSpLzsZccC7pD1wyjwdXlMjmal9EMyvsY4czoWXODXMgoa1yDZEa5ou2TBXLS Zs/oBHwzFil4rFSULy7aEw8cj8RhGVz8WMHveDB8jYaV4NnqiBmh1lt88BVmNtuSyvej xXesa1D2x6JPZdNNfWebAbtdwLpopQ75jSMwya1NvOh8iko6WYhcVI/qv/pHzaUuaSke FZpGwGndeGiiINwdYFzXwjOvAyZYYQ5/QO+jSJbch0LXKBTyTqoA9KBoFyxhI242FNqg M1yEShwXwpCIEhkJ6BPyKf1BxLn9pWIaokySNRDzHCBL0O6ywkm4WuWA4lmeJqbns05/ u3CQ== X-Gm-Message-State: AKGB3mI2hysF99DmXP7CmC3RIKiZaEbaTK1P4FcIojqZgp57rLkNQBXO 9oNxLLM/ct3OGWsLptWLaTQVHQ== X-Google-Smtp-Source: ACJfBovq2v7TIbwiFy52FYgjiemScpYYGJfKyqDkydAwfGwvnhRE4RefUTSorgBlSRUdaZqDZfDJfQ== X-Received: by 10.80.134.37 with SMTP id o34mr5173727edo.37.1515173920424; Fri, 05 Jan 2018 09:38:40 -0800 (PST) Received: from [10.10.1.111] ([185.97.61.1]) by smtp.gmail.com with ESMTPSA id e46sm4760128edb.93.2018.01.05.09.38.39 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Fri, 05 Jan 2018 09:38:39 -0800 (PST) Subject: Re: svn commit: r327559 - in head: . sys/net To: Eugene Grosbein , src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org References: <201801042005.w04K5liB049411@repo.freebsd.org> <5A4E9397.9000308@grosbein.net> <5A4EDC62.50508@grosbein.net> <5A4F824C.1060405@grosbein.net> <97d173fb-4f47-609d-8319-07282a283473@multiplay.co.uk> <5A4FB2E0.4010603@grosbein.net> From: Steven Hartland Message-ID: <4e72bc1d-e535-d3e2-eba3-3d9bd575ba4f@multiplay.co.uk> Date: Fri, 5 Jan 2018 17:38:40 +0000 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:52.0) Gecko/20100101 Thunderbird/52.5.2 MIME-Version: 1.0 In-Reply-To: <5A4FB2E0.4010603@grosbein.net> Content-Language: en-US Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit X-Content-Filtered-By: Mailman/MimeDel 2.1.25 X-BeenThere: svn-src-all@freebsd.org X-Mailman-Version: 2.1.25 Precedence: list List-Id: "SVN commit messages for the entire src tree \(except for " user" and " projects" \)" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 05 Jan 2018 17:38:42 -0000 On 05/01/2018 17:16, Eugene Grosbein wrote: > >>> That is, there is no guarantee of persistance of flowid of incoming packets >>> as they can be received with distinct ports of lagg being distinct hardware >>> computing flowid differently. Some ports may not support RSS at all. >>> We should not use incoming hardware flowid for anything by default in case of TCP. >> I don't believe your statement about persistence of flowid due to the use of variant ports is correct >> as LACP states that packets from the same flow "should" under normal conditions (no failure) be received on the same port. > It still does not guarantee that and you miss opportunity of network failures that can easily change flowid of incoming packets. Correct, but that's not the normal behavior so the chances of seeing any impact of out of order packets is very small. > >> In the case where the HW doesn't support RSS, then flowid should either always be unset or be set by OS to consistent value hence that should function as expected. >> >> That said I don't disagree that all hostA -> hostB should use Manual hash, as I can't see anyway to use to HW hash, >> however the ports in your example are wrong > Yes, I stand corrected (just copied your example and adjusted it incompletly). > >>> Why do you mix flowid of incoming stream with flowid of outgoing stream? >>> >> I expect this was done so we don't have the overhead of calculating a packet hash for every outgoing packet >> i.e. its an optimization, however I believe this is only possible for the destination host which always >> has a valid flowid, and not for the source host. > How do you know that flowid of incoming packet is preserved on outgoing path? It should not. https://github.com/freebsd/freebsd/blob/master/sys/netinet/ip_output.c#L234     Regards     Steve