From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-relay230.hrz.tu-darmstadt.de (mail-relay230.hrz.tu-darmstadt.de [IPv6:2001:41b8:83f:1610::230]) (using TLSv1.2 with cipher ADH-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.bufferbloat.net (Postfix) with ESMTPS id CF4133B29E; Wed, 21 Apr 2021 12:07:14 -0400 (EDT) Received: from kommail.kom.e-technik.tu-darmstadt.de (kommail.kom.e-technik.tu-darmstadt.de [IPv6:2001:41b8:810:10::5]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by mail-relay230.hrz.tu-darmstadt.de (Postfix) with ESMTPS id 4FQQRh2tgXz43h6; Wed, 21 Apr 2021 18:07:12 +0200 (CEST) Received: by kommail.kom.e-technik.tu-darmstadt.de (Postfix, from userid 998) id DA6EB2A02C0; Wed, 21 Apr 2021 18:07:11 +0200 (CEST) To: Dave Taht , bloat , codel@lists.bufferbloat.net References: From: Ralf Kundel Autocrypt: addr=ralf.kundel@kom.tu-darmstadt.de; keydata= xsFNBFpUkv4BEADGpbmZqcCcqcCkx3z9heoUPOuwufD8f7sRXxPGof7oGlQyhQp5OYglPLuj /jneuJRCnOeIX6K1yam2eNegbu5+yhw2ZTH+WC6z9ODVaANW7K7fKQAjGWnwC4wceP5eJQPd YuGEq/8nQwngO+G4YjYkOOfmAKCEBftT0J6Mxz/q3CL8sM/xTC7IVWtuh0AfiBa9xvGO3YOt gViTNEqqQcwsSq1yLFuIBZpNJRbbH/qSpQ2IeFseW6WZChrr9NC+mjq8y79jvxE5iyH63whZ aHbYnei5y0htIWz740qgoucydZi3vZ5HurVntl5//vS5fyq+CH4A859422m+wVd3Uwijfqf3 LTVGFh+5t0d1Hx5Rd1l+4D3ox0Xc128G7N/XFCMPMemjUtn3hG5BYSZZBVSL2HFo+LZqmRWN b8DheqtqrxpvWBdSfE5+BXD3y+p+8tc94sigH1iLVQh3Hq0b9nAyrAstoeeSO1L1FZTg8dk9 WYEYrzgHxQK3VJGlPA7snc1lxJTAni9S58WL7mGeydbsD3VrFuyWT1lfO3LWjS79CjWaxinU xfKhdvQ8fNmTry36oqNM8/BdrVlL9uGlduUX8Q18uNbtI5q3ogNWPdoHlzey1tKOBPRAtChK kgHsxWhpKncQfi1jvuCRIsLRK5tAIccQtHXeb0zcJGeNX10M7QARAQABzS1SYWxmIEt1bmRl bCA8cmFsZi5rdW5kZWxAa29tLnR1LWRhcm1zdGFkdC5kZT7CwasEEwEIAD4WIQTH9/VYlNU6 1AecaCVy7MhoQ4AzfAUCWlSS/gIbIwUJCWYBgAULCQgHAgYVCAkKCwIEFgIDAQIeAQIXgAAh CRBy7MhoQ4AzfBYhBMf39ViU1TrUB5xoJXLsyGhDgDN8/zsQALXmaZ0qkCe3pUE6yPhJXXoD ugBCAi5w1aAN3OB2HDMeTOzyOxeAxJZi9yorgSXSLGlwtfRiSkWuLaUJ2jleAbJ4ULw9vNpj FwFqjJgYYQUVJ5cgA6/NGl7VQA7RoSsI7UfpKi36MeLDYtbbvGqkBXEMza6Ux8WPo2au4PGh SChGnHvvEiJMz4X5ISOlv71WSH16WeBTIrtTotcwJvpPyT6zQ70ja9r44gSXJmIuPzzCJJb2 2SSENjHORIgmn4zG3rfqzKMI8lPdoCrFJRuJsjk3kTjttR4xK/g00Dfnh5SHPEMl2EIKD0NI Xsuo4ebkUx6DEzwKyhuiZBIRf2LiOrMHF6rYWRbvqPkZMrQEZKd8SccU5GS/WSK3trah73kn q+jiGM8+9RAdu86+A2Ip4oNFRUFBz/OCZin9lhYFKipjtLPSfJSWzSXTDsuaoAAG31IfKkNU v82HwD1E31roaUXW8rcB5QX+5E183KSJ7aczyzWjg0qnpHFANxDYIjzf5FCluOGbI0GS+4Gh zSp4FvusWFk2856q9CWEWyHKWLpRiPhu81zIDs7L1AU93fdxYtsW7MLPKPAO3ElYmSpn6mQ3 m8tCyaYpKDEFEPOUcrfH11RHhcylBryS2R97wtCtXTREWSbradnMxlA/td4C8KrssOV/C4u0 FXuayfqUixc+zsFNBFpUkv4BEAC03CaqQG2UI49qSEjhcbhlTLcrlnBe+JfESmbC/0ods9aY JzF07IK1TJGt3HuUL+OEzxb6AgWncwQY1g33TwhaDa3OKzUT9AsytYz941RpZrFqAraaOlyX vz99jWZr2cC7Iy/MET7GylE35gHwqMKC9LGkzjIODce0RpynBjSY9n0YX8fOEpT/B5lr+O1p MuOVGrahO793Ca25HcTuLc1tHLeoJUnzlc7FfdCog/MCgrqxRYpHwkcGJPS/0JgS5oWLr3yF DMu01DR1SR+XinyyTntquDhCZmkMg9PtZFd1hwaAuoXF2z/Xf7pL2FkqKj13PidRkUCsuBfy Bjy0al7OYBsGUD8hKpj+apNOMQIOwmg3pGQPG9v7WHiacRUdotX50oFPAszcP5jhFK4v3E7F /D+zlq4M9MV21rTABk7K1Abi+vHlEtWhcM48hpKqZPAwoeCxYAbXaIM0rrKlugrG1GVnu6FS ziIL9xEM4LWWi8VKtXXKXJ5tv+tWmccswg6WP+jwgwzrP5FLkKISdY4RFhfGXnp4WKXfgZhI jWdFnstR7Cc3wBKDs+aL3RqSomYSL4W3xcYLBZT+yvwL/l1i6hFw3x93lOBCEEm72nCwInjr lPingqrygrxNuUBvwg7v7gbbWmR29aLCGXGxB51hoR494gtGI620BK4h1qZLaQARAQABwsGT BBgBCAAmFiEEx/f1WJTVOtQHnGglcuzIaEOAM3wFAlpUkv4CGwwFCQlmAYAAIQkQcuzIaEOA M3wWIQTH9/VYlNU61AecaCVy7MhoQ4AzfAeeD/4i3cuuIKZATipBdQMtpHS3vjHjWKmNlGVi WozxIbPXQIOY7BBrfaP1umCW6vC0B/MsmB8QUNSJWJlCVTrL6J8Z//N7fgyHgBTfYRaqiopt 9FUfQt9gJ6owIp2sm0sDcVHkvMvbBFfPxuFebzeioTVbIoCYrrgT3fJXJTerQhPpX6ex8bHl cIFe56CkxD22z5X5Azd735H/xebHip/JRP8TM7QFAkXinF3LD0vUOaFLlh92a7b93jRC3W7U rD/6R+rw0pT9uuXu51w4jNZz8rv3g6ae5xpKhI1qlQKBMocrtyrAG4ZthWRW2y0m+VfmzweU GXZcYCatEkBHnw3GEbDvdZMmaSJT+NT/zhUDeCuNShCr27u5y6pgLsVqouvJgFO09UNqNHK7 j9wTuiTv39fMTM2KBEdnRToFcWNh7SMs6w0r4HC0zgHGVuC/C8KUk77GWedwf/P1dtutueN0 tFFGcYqhbzxJawMSuHt/v9l93AswYWPCTIai+w6UUyZ2wN9rxFwdZ+MXDpsDRYixoEG2fhDI efK5OlZ8Op+pgHMSMwNTZMrtkKo+1JXQtY9JRm7e4BJlPzZN+FpL/UU2xrNFCacYTL5kIFxa GvKQkLWh7WK5HIgu7bjrYg4cZ6Rgw5/t0IY5Uv1tZHkqW6/v4ZBUp9e9RIiZLYHVZyIYxOrp zA== Message-ID: <0e2c44fc-85ee-8be8-5f6b-1a71141cf07f@kom.tu-darmstadt.de> Date: Wed, 21 Apr 2021 18:07:08 +0200 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Content-Language: en-US Subject: Re: [Bloat] Pie not fully implementable on tofino p4 X-BeenThere: bloat@lists.bufferbloat.net X-Mailman-Version: 2.1.20 Precedence: list List-Id: General list for discussing Bufferbloat List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 21 Apr 2021 16:07:14 -0000 Hi, regarding the question: how timestamps come from ingress to egress pipe? Well this depends (on the P4 abstraction) on the P4 version you use. As far as I remember (it is a long time ago) in P4_14 metadata (which can store the timestamp) are handed over implicitly from ingress to egress. In P4_16 you have do do this explicitly in the Deparser of Ingress and Parser of Egress: Simply said you just write the timestamp before the Ethernet header. You can see this here in line 64 to 80: https://github.com/ralfkundel/p4-codel/blob/master/targets/tofino/srcP4/l1switchCodel.p4 best, Ralf Am 21.04.21 um 04:42 schrieb Dave Taht: > https://www.comsys.rwth-aachen.de/fileadmin/papers/2021/2021-kunze-aqm-tofino-p4.pdf > > For a codel comparison, see: > > https://arxiv.org/pdf/2010.04528v1.pdf > > Where the authors show that fq_codel is feasible on the PISA platform... > > but a direct comparison between the two papers is not possible. What I > don't understand about the above paper is how codel timestamps are > passed from ingress to egress. > -- ________________________________________________ Ralf Kundel, M.Sc. Technical University of Darmstadt Dept. of Electrical Engineering and Information Technology Multimedia Communications Lab (KOM) Adaptive Communication Systems Group (ACS) Postal address: TU Darmstadt, FB 18, KOM, Rundeturmstr. 10, 64283 Darmstadt, Germany Location: S3|20 - 216 Tel: +49 6151 16-20855 Email: Ralf.Kundel@kom.tu-darmstadt.de Web: http://www.kom.tu-darmstadt.de ___________________________________________________________