From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Serge E. Hallyn" Subject: Re: stop checkpointed process Date: Sun, 29 Nov 2009 09:45:35 -0600 Message-ID: <20091129154535.GA1115@us.ibm.com> References: <2f0d4790911261815s6ba92aa1w9dce17b0c582bb62@mail.gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Content-Disposition: inline In-Reply-To: <2f0d4790911261815s6ba92aa1w9dce17b0c582bb62-JsoAwUIsXosN+BqQ9rBEUg@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: Jianwei Liao Cc: containers-qjLDD68F18O7TbgM5vRIOg@public.gmane.org List-Id: containers.vger.kernel.org Quoting Jianwei Liao (liaotoad1-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org): > hi all, > I am using ckpt-v18, everything is fine. > i have read some of the code of ckpt, but i was wondering that where does > kernel module to stop the checkpointee? (something related to context?) i > hope you can point me out how to find such stuff. > Can i use SIGSTOPand SIGCONT to do such things? > Thank you very much. > Liao Userspace should do this in advance by using the freezer cgroup. So for instance if you are wanting to checkpoint /usr/bin/myapp, then one way to do it is: (terminal 1) mkdir -p /cgroup mount -t cgroup -o freezer freezer /cgroup mkdir /cgroup/myapp (terminal 2) echo $$ > /cgroup/myapp/tasks /usr/bin/myapp (terminal 1) echo FROZEN > /cgroup/myapp/freezer.state pid=`pidof myapp` checkpoint $pid > myapp.ckpt echo THAWED > /cgroup/myapp/freezer.state If the application hasn't been frozen using the freezer cgroup, then sys_checkpoint() will return -EBUSY. -serge