From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tejun Heo Subject: Re: cgroup: status-quo and userland efforts Date: Tue, 9 Apr 2013 12:46:40 -0700 Message-ID: <20130409194640.GK6186@mtj.dyndns.org> References: <20130406012159.GA17159@mtj.dyndns.org> <20130409095024.GI25576@redhat.com> <20130409193851.GJ6186@mtj.dyndns.org> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=x-received:sender:date:from:to:cc:subject:message-id:references :mime-version:content-type:content-disposition:in-reply-to :user-agent; bh=2H+M4T+JNxiNzohjtRCzkZhqOzJ8JDaCUjSAZnFAgwA=; b=DgIwQQwgsCwPMvQ/NWYPHRWaF86NyS3WdcbNDWUmsqKPMeHvDf6vMO/q2PUV48rh0X 6R9/CBmTDn8Cc1C0GmJUiLSMpNG4nLQom5xeVW+4VGsJPMvE+pV6hrIWSnbUm08zOhSQ 8fy6F2aXRQ3WCElg2pqv2nZfYK6yRmkaEO+SYCERohynHZRRryXLIkpHHCCLME7rwx38 g4Izwy+HRG/lX/DNTa3SGQKkb3hH4O5+F0MCDj2eqvCeJ/sOiTYe/4r8pkEsQ6CN7pdn ps+4BrmyOE7WkJt8m/7ekJ011N2KZ6NIDJxw3H6AGoHc72nvM32B+fmA/bZNiqqX8lK0 c1Zg== Content-Disposition: inline In-Reply-To: <20130409193851.GJ6186-9pTldWuhBndy/B6EtB590w@public.gmane.org> List-Id: 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: "Daniel P. Berrange" Cc: jpoimboe-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, containers-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org, Kay Sievers , lpoetter-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org, workman-devel-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org, dhaval.giani-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org, cgroups-u79uwXL29TY76Z2rM5mHXA@public.gmane.org A bit of addition. On Tue, Apr 09, 2013 at 12:38:51PM -0700, Tejun Heo wrote: > > We need to make the distribute approach work in order to support > > containers, which requiring them to have a back-channel open to > > the host userspace. If we can do that, then we've solved the problem Why is back-channel such a bad thing? Even fully virtualized environments do special things to communicate with the host (the whole stack of virt drivers). It is sub-optimal and pointless to make everything completely transparent. There's nothing wrong with the basesystem knowing that they're inside a container or a virtualized environment, so I don't understand why a back-channel is such a big problem. Thanks. -- tejun