From mboxrd@z Thu Jan 1 00:00:00 1970 From: Kir Kolyshkin Subject: Re: [Devel] Re: [RFC] network namespaces Date: Wed, 06 Sep 2006 21:37:36 +0400 Message-ID: <44FF0760.1040600@openvz.org> References: <20060815182029.A1685@castle.nmd.msu.ru> <20060816115313.GC31810@sergelap.austin.ibm.com> <44FD7CF0.4030009@fr.ibm.com> <20060905165328.GA17317@MAIL.13thfloor.at> <44FE907F.7090508@fr.ibm.com> <20060906165642.GA26202@MAIL.13thfloor.at> Mime-Version: 1.0 Content-Type: text/plain; charset=KOI8-R; format=flowed Content-Transfer-Encoding: 7bit Cc: Daniel Lezcano , Andrew Morton , netdev@vger.kernel.org, sam@vilain.net, Andrey Savochkin , alexey@sw.ru, Linux Containers , "Serge E. Hallyn" Return-path: Received: from [62.205.161.221] ([62.205.161.221]:54933 "EHLO kir.sacred.ru") by vger.kernel.org with ESMTP id S1751788AbWIFRgX (ORCPT ); Wed, 6 Sep 2006 13:36:23 -0400 To: devel@openvz.org In-Reply-To: <20060906165642.GA26202@MAIL.13thfloor.at> Sender: netdev-owner@vger.kernel.org List-Id: netdev.vger.kernel.org Herbert Poetzl wrote: > my point (until we have an implementation which clearly > shows that performance is equal/better to isolation) > is simply this: > > of course, you can 'simulate' or 'construct' all the > isolation scenarios with kernel bridging and routing > and tricky injection/marking of packets, but, this > usually comes with an overhead ... > Well, TANSTAAFL*, and pretty much everything comes with an overhead. Multitasking comes with the (scheduler, context switch, CPU cache, etc.) overhead -- is that the reason to abandon it? OpenVZ and Linux-VServer resource management also adds some overhead -- do we want to throw it away? The question is not just "equal or better performance", the question is "what do we get and how much we pay for it". Finally, as I understand both network isolation and network virtualization (both level2 and level3) can happily co-exist. We do have several filesystems in kernel. Let's have several network virtualization approaches, and let a user choose. Is that makes sense? * -- http://en.wikipedia.org/wiki/TANSTAAFL