[CRIU] checkpointing a docker container and restoring the process to a new container

[Ross Boucher]

Yeah, but I think there are other problems as well. I'm trying the same
restore process with a more complex program and seeing odd behavior: the
process gets restored, but it seems to be hung. I have a thread in this
program that just prints in a loop every second and it never prints after
being restored (again, this works fine if I restore into the same
container).

On Fri, Apr 24, 2015 at 6:59 AM, Pavel Emelyanov <xemul at parallels.com>
wrote:

> On 04/24/2015 04:47 PM, Ross Boucher wrote:
> > inherit_fd is being used -- this example works fine if I restore to the
> same container,
> > it's only breaking now that I'm attempting to restore into a completely
> different container.
>
> So the pipe doesn't get inherited when you restore into different
> container?
>
> > On Fri, Apr 24, 2015 at 4:50 AM, Pavel Emelyanov <xemul at parallels.com
> <mailto:xemul at parallels.com>> wrote:
> >
> >     On 04/24/2015 12:11 AM, Ross Boucher wrote:
> >     > Another update: I was intrigued by the exit code (which implies
> SIGPIPE?), since the docker process
> >     > I was running was indeed piping:
> >     >
> >     >     /bin/sh -c 'i=0; while true; do echo $i; i=$(expr $i + 1);
> sleep 3; done'
> >     >
> >     > I tried the same process of checkpointing in one container and
> restoring to another by writing to a file instead:
> >     >
> >     >     /bin/sh -c 'i=0; while true; do echo $i > /tmp/foo; i=$(expr
> $i + 1); sleep 3; done'
> >     >
> >     > And this worked correctly! So I've narrowed it done some more, and
> I'll continue to look into it.
> >
> >     If these are pipes indeed (docker terminals?) then the --inherit-fd
> option should be used.
> >     Saied (from Google) did some work doing this for docker+criu, he can
> shed more light, but
> >     he's on vacation right now :)
> >
> >     -- Pavel
> >
> >
>
>
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