From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Ahern Subject: Re: [RFC PATCH net-next v2 0/5] netns: allow to identify peer netns Date: Fri, 26 Sep 2014 13:15:10 -0600 Message-ID: <5425BB3E.10700@gmail.com> 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> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii"; Format="flowed" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <54256CCB.4000709-pdR9zngts4EAvxtiuMwx3w@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: containers-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org Errors-To: containers-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org To: nicolas.dichtel-pdR9zngts4EAvxtiuMwx3w@public.gmane.org, Cong Wang Cc: netdev , containers-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org, "linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , Andy Lutomirski , Stephen Hemminger , "Eric W. Biederman" , linux-api-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Andrew Morton , David Miller List-Id: linux-api@vger.kernel.org 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. David