From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sukadev Bhattiprolu Subject: Re: restart (mktree) program usage Date: Wed, 16 Sep 2009 18:35:46 -0700 Message-ID: <20090917013546.GA30161@us.ibm.com> References: <20090909055636.GA27622@us.ibm.com> <4AA82B7C.8080107@librato.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Content-Disposition: inline In-Reply-To: <4AA82B7C.8080107-RdfvBDnrOixBDgjK7y7TUQ@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: Oren Laadan Cc: Containers List-Id: containers.vger.kernel.org Oren Laadan [orenl-RdfvBDnrOixBDgjK7y7TUQ@public.gmane.org] wrote: | | | Sukadev Bhattiprolu wrote: | > I have a usage question on the 'restart' (formerly mktree) program. | > | > In the following container c/r case: | > | > - create a container | > - log in to the container, | > - restore filesystem(s) from snapshot | > - restart application from checkpoint | | FWIW, I'd expect that future versions of 'restart' will be capable | of doing this entire setup, (filesystem(s) included), as it matures. | | Note that this use case that you suggest will only work to restart | subtrees; it is unsuitable for full containers (with pids) because | the pid of init (1) will already be in use. True. But if originally the application was started as: Create container Login to contaienr Set up filesystem Start application The application would not be using the pid 1 right - even if the application was started from an rc script in the container ? | | Perhaps we should think of some "plugin" architecture for 'restart' | that will allow the user to ask it to execute some work at between | creating a new container and actually restarting into it ? Yes, that would be really useful I think for things like restoring file system to its snapshot. Without that there is somewhat of an assymetry in starting an application in a container and restarting it from a checkpoint.