From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751609AbcGRR6s (ORCPT ); Mon, 18 Jul 2016 13:58:48 -0400 Received: from mga04.intel.com ([192.55.52.120]:1518 "EHLO mga04.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751364AbcGRR6o (ORCPT ); Mon, 18 Jul 2016 13:58:44 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.28,385,1464678000"; d="scan'208";a="997683712" From: "Liang, Kan" To: Tom Herbert CC: Florian Westphal , "davem@davemloft.net" , "linux-kernel@vger.kernel.org" , "intel-wired-lan@lists.osuosl.org" , "netdev@vger.kernel.org" , "Kirsher, Jeffrey T" , "mingo@redhat.com" , "peterz@infradead.org" , "kuznet@ms2.inr.ac.ru" , "jmorris@namei.org" , "yoshfuji@linux-ipv6.org" , "kaber@trash.net" , "akpm@linux-foundation.org" , "keescook@chromium.org" , "viro@zeniv.linux.org.uk" , "gorcunov@openvz.org" , "john.stultz@linaro.org" , "aduyck@mirantis.com" , "ben@decadent.org.uk" , "decot@googlers.com" , "Brandeburg, Jesse" , "andi@firstfloor.org" Subject: RE: [RFC PATCH 00/30] Kernel NET policy Thread-Topic: [RFC PATCH 00/30] Kernel NET policy Thread-Index: AQHR4QAYnLk7kPdiS0Cr9oejSYLaHaAdxziAgACI/vD//4xLAIAAmdGg Date: Mon, 18 Jul 2016 17:58:39 +0000 Message-ID: <37D7C6CF3E00A74B8858931C1DB2F07712C197C5@SHSMSX103.ccr.corp.intel.com> References: <1468824984-65318-1-git-send-email-kan.liang@intel.com> <20160718151841.GA19066@breakpoint.cc> <37D7C6CF3E00A74B8858931C1DB2F07712C1968E@SHSMSX103.ccr.corp.intel.com> In-Reply-To: Accept-Language: zh-CN, en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-titus-metadata-40: eyJDYXRlZ29yeUxhYmVscyI6IiIsIk1ldGFkYXRhIjp7Im5zIjoiaHR0cDpcL1wvd3d3LnRpdHVzLmNvbVwvbnNcL0ludGVsMyIsImlkIjoiMDg3YWE2NzQtMDExOC00ODE4LTllODMtNGIzY2QyMDRmYzcxIiwicHJvcHMiOlt7Im4iOiJDVFBDbGFzc2lmaWNhdGlvbiIsInZhbHMiOlt7InZhbHVlIjoiQ1RQX0lDIn1dfV19LCJTdWJqZWN0TGFiZWxzIjpbXSwiVE1DVmVyc2lvbiI6IjE1LjkuNi42IiwiVHJ1c3RlZExhYmVsSGFzaCI6InZJVFYwaVwvTlkyVno2bzNWMnJmYndjdlhcLzJZYlZ0cEZQNHB1QzNLTStoMD0ifQ== x-ctpclassification: CTP_IC x-originating-ip: [10.239.127.40] Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Transfer-Encoding: 8bit X-MIME-Autoconverted: from base64 to 8bit by mail.home.local id u6IHx6mu010786 > On Mon, Jul 18, 2016 at 5:51 PM, Liang, Kan wrote: > > > > > >> > > >> > It is a big challenge to get good network performance. First, the > >> > network performance is not good with default system settings. > >> > Second, it is too difficult to do automatic tuning for all possible > >> > workloads, since workloads have different requirements. Some > >> > workloads may want > >> high throughput. > >> > >> Seems you did lots of tests to find optimal settings for a given base policy. > >> > > Yes. Current test only base on Intel i40e driver. The optimal settings > > should vary for other devices. But adding settings for new device is not > hard. > > > The optimal settings are very dependent on system architecture (NUMA > config, #cpus, memory, etc.) and sometimes kernel version as well. A > database that provides best configurations across different devices, > architectures, and kernel version might be interesting; but beware that that is > a whole bunch of work to maintain, Either way policy like this really should > be handled in userspace. The expression "optimal" I used here is not accurate. Sorry for that. The NET policy tries to get good (near optimal) performance by very simple configuration. I agree that there are lots of dependencies for the optimal settings. But most of the settings should be very similar. The near optimal performance by applying those common settings are good enough for most users. We don't need to maintain a database for configurations across devices/architectures/kernel version... Thanks, Kan