openwhisk-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Carlos Santana <csantan...@gmail.com>
Subject Re: Recover image pulls by trying to run the container anyways.
Date Fri, 29 Jun 2018 03:15:12 GMT
+1


On Wed, Jun 27, 2018 at 11:43 AM Rodric Rabbah <rodric@gmail.com> wrote:

> In general I think this is a good change - but minor nit that "latest" in
> docker doesn't mean pull the latest tag.
>
> -r
>
>
>
> On Wed, Jun 27, 2018 at 7:35 AM, Markus Thoemmes <
> markus.thoemmes@de.ibm.com
> > wrote:
>
> > Dear OpenWhiskers,
> >
> > when using Blackbox actions, whenever OpenWhisk creates a new container
> > "docker pull" is executed to get the image for that container explicitly.
> > It's implemented that way to guarantee new containers are always on the
> > latest code-state that was pushed to Dockerhub.
> >
> > Now for rapid prototyping that is a nice feature, for production
> workloads
> > it might not be. Essentially this means that your production workload is
> > now dependend on Dockerhub being up and running fine, even though your
> > images might already have been pulled to all invoker machines necessary.
> >
> > I therefore propose the following behavioral change:
> >
> > 1. Iff the user specifies "latest" as the image tag explicitly (or
> > implicitly by not specifying a tag at all), the behavior will stay the
> same
> > as above. If "docker pull" fails, the whole container bringup process
> fails
> > and the user is given an error. That ensures, that for these workloads
> > (which I consider development/prototyping) workloads, the user can
> > deterministically know, that after an action update, each cold-start
> > contains the very latest image or errors out.
> > 2. For all actions with a tag different than "latest", they are
> considered
> > production workloads. It is considered best-practice to not use "latest"
> > for production images and expected that the user versions their images
> > through the tags. OpenWhisk will still try to pull each time it creates a
> > new container, for good measure. If the pull fails, the system will still
> > try to "docker run" the container. If an image with that tag is already
> > available locally, it will be picked up and the action runs just fine.
> This
> > does not guarantee the latest code-state under all circumstances, but
> it's
> > much more stable for applications in production.
> >
> > An implementation of the proposal can be found here:
> > https://github.com/apache/incubator-openwhisk/pull/3813
> >
> > Feedback is very welcome :)
> >
> > Cheers,
> > -m
> >
> >
>

Mime
  • Unnamed multipart/alternative (inline, None, 0 bytes)
View raw message