From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755903AbaIZTeo (ORCPT ); Fri, 26 Sep 2014 15:34:44 -0400 Received: from out01.mta.xmission.com ([166.70.13.231]:53026 "EHLO out01.mta.xmission.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754281AbaIZTel (ORCPT ); Fri, 26 Sep 2014 15:34:41 -0400 From: ebiederm@xmission.com (Eric W. Biederman) To: David Ahern Cc: nicolas.dichtel@6wind.com, Cong Wang , netdev , containers@lists.linux-foundation.org, "linux-kernel\@vger.kernel.org" , linux-api@vger.kernel.org, David Miller , Stephen Hemminger , Andrew Morton , Andy Lutomirski References: <1411478430-4989-1-git-send-email-nicolas.dichtel@6wind.com> <54228D87.3070309@6wind.com> <5422F0F4.6000709@6wind.com> <5423D80B.9060500@6wind.com> <54256CCB.4000709@6wind.com> <5425BB3E.10700@gmail.com> Date: Fri, 26 Sep 2014 12:34:16 -0700 In-Reply-To: <5425BB3E.10700@gmail.com> (David Ahern's message of "Fri, 26 Sep 2014 13:15:10 -0600") Message-ID: <87mw9myy4n.fsf@x220.int.ebiederm.org> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/24.3 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain X-XM-AID: U2FsdGVkX19U38EMx7rEYS9W6ViK4eMakoa9EoTOKzc= X-SA-Exim-Connect-IP: 98.234.51.111 X-SA-Exim-Mail-From: ebiederm@xmission.com X-Spam-Report: * -1.0 ALL_TRUSTED Passed through trusted hosts only via SMTP * 0.7 XMSubLong Long Subject * 0.0 T_TM2_M_HEADER_IN_MSG BODY: No description available. * -0.0 BAYES_40 BODY: Bayes spam probability is 20 to 40% * [score: 0.3322] * -0.0 DCC_CHECK_NEGATIVE Not listed in DCC * [sa06 1397; Body=1 Fuz1=1 Fuz2=1] * 1.0 T_XMDrugObfuBody_08 obfuscated drug references * 0.0 T_TooManySym_01 4+ unique symbols in subject X-Spam-DCC: XMission; sa06 1397; Body=1 Fuz1=1 Fuz2=1 X-Spam-Combo: ;David Ahern X-Spam-Relay-Country: Subject: Re: [RFC PATCH net-next v2 0/5] netns: allow to identify peer netns X-Spam-Flag: No X-SA-Exim-Version: 4.2.1 (built Wed, 24 Sep 2014 11:00:52 -0600) X-SA-Exim-Scanned: Yes (on in02.mta.xmission.com) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org David Ahern writes: > On 9/26/14, 7:40 AM, Nicolas Dichtel wrote: >>> >>> >>> No, I don't want to monitor anything. Even if I wanted, I would just >>> start one >>> daemon in each netns instead of one for all. >> Ok you don't want, but some other people (not only me) want it! And >> having one >> daemon per netns does not scale: there are scenarii with thousand netns >> which >> are dynamically created and deleted. > > An example of the scaling problem using quagga (old but still seems to be a > relevant data point): > > > https://lists.quagga.net/pipermail/quagga-users/2010-February/011351.html > > "2k VRFs that would be 2.6G" > > And that does not include the overhead of each namespace -- roughly > 200kB/namespace on one kernel I checked (v3.10). So that's a ballpark of 3G of > memory. Resetting the conversation just a little bit. When I wrote the "ip netns" support I never expected that all applications would want to run in a specific network namespace. All that is needed is one socket per network namespace. Furthermore one socket or one procesess per network namespaces is completely orthogonal to the patches presented. I do not see a identifying where the far end of a veth pair or similar set of networking objects as anything that even closely resembles a path to a using only a single socket. So I think this whole subthread is quite silly and grossly off track. Eric