From mboxrd@z Thu Jan 1 00:00:00 1970 From: Cedric Le Goater Subject: Re: [PATCH 1/3] powerpc: bare minimum checkpoint/restart implementation Date: Fri, 13 Mar 2009 16:42:20 +0100 Message-ID: <49BA7EDC.1000705@free.fr> References: <1233182478-27113-1-git-send-email-ntl@pobox.com> <1233182478-27113-2-git-send-email-ntl@pobox.com> <49814FA2.9060108@cs.columbia.edu> <20090129214035.GB6913@localdomain> <20090217010355.58afd5cf@thinkcentre.lan> <49B9D37A.1070503@cs.columbia.edu> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <49B9D37A.1070503-eQaUEPhvms7ENvBUuze7eA@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-qjLDD68F18O7TbgM5vRIOg@public.gmane.org, linuxppc-dev-mnsaURCQ41sdnm+yROfE0A@public.gmane.org, Nathan Lynch List-Id: containers.vger.kernel.org > More specifically, I envision restart to work like this: > > 1) user invokes user-land utility (e.g. "cr --restart ..." > 2) 'cr' will create a new container > 3) 'cr' will start a child in that container process 1 in its private namespaces. > 4) child will create rest of tree (in kernel or in user space - tbd) > 5) each task in that tree will restore itself > 6) 'cr' monitors this process > 7) if all goes well - 'cr' report ok. > 8) if something goes bad, 'cr' notices and notifies caller/user that's MCR implementation of restart. > so tasks that are restarting may just as well die badly - we don't care. just sigkill them, but at end, before releasing the container from a frozen state, we have to make sure the right number of tasks have restarted ... so you need to track them along the way. C. From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mtagate4.de.ibm.com (mtagate4.de.ibm.com [195.212.29.153]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client CN "mtagate4.de.ibm.com", Issuer "Equifax" (verified OK)) by ozlabs.org (Postfix) with ESMTPS id 86E28DE05A for ; Sat, 14 Mar 2009 02:42:30 +1100 (EST) Received: from d12nrmr1607.megacenter.de.ibm.com (d12nrmr1607.megacenter.de.ibm.com [9.149.167.49]) by mtagate4.de.ibm.com (8.14.3/8.13.8) with ESMTP id n2DFgPS7139332 for ; Fri, 13 Mar 2009 15:42:25 GMT Received: from d12av02.megacenter.de.ibm.com (d12av02.megacenter.de.ibm.com [9.149.165.228]) by d12nrmr1607.megacenter.de.ibm.com (8.13.8/8.13.8/NCO v9.2) with ESMTP id n2DFgONI4214794 for ; Fri, 13 Mar 2009 16:42:24 +0100 Received: from d12av02.megacenter.de.ibm.com (loopback [127.0.0.1]) by d12av02.megacenter.de.ibm.com (8.12.11.20060308/8.13.3) with ESMTP id n2DFgNU6008568 for ; Fri, 13 Mar 2009 16:42:23 +0100 Message-ID: <49BA7EDC.1000705@free.fr> Date: Fri, 13 Mar 2009 16:42:20 +0100 From: Cedric Le Goater MIME-Version: 1.0 To: Oren Laadan Subject: Re: [PATCH 1/3] powerpc: bare minimum checkpoint/restart implementation References: <1233182478-27113-1-git-send-email-ntl@pobox.com> <1233182478-27113-2-git-send-email-ntl@pobox.com> <49814FA2.9060108@cs.columbia.edu> <20090129214035.GB6913@localdomain> <20090217010355.58afd5cf@thinkcentre.lan> <49B9D37A.1070503@cs.columbia.edu> In-Reply-To: <49B9D37A.1070503@cs.columbia.edu> Content-Type: text/plain; charset=ISO-8859-1 Cc: containers@lists.osdl.org, linuxppc-dev@ozlabs.org, Nathan Lynch List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , > More specifically, I envision restart to work like this: > > 1) user invokes user-land utility (e.g. "cr --restart ..." > 2) 'cr' will create a new container > 3) 'cr' will start a child in that container process 1 in its private namespaces. > 4) child will create rest of tree (in kernel or in user space - tbd) > 5) each task in that tree will restore itself > 6) 'cr' monitors this process > 7) if all goes well - 'cr' report ok. > 8) if something goes bad, 'cr' notices and notifies caller/user that's MCR implementation of restart. > so tasks that are restarting may just as well die badly - we don't care. just sigkill them, but at end, before releasing the container from a frozen state, we have to make sure the right number of tasks have restarted ... so you need to track them along the way. C.