Question: Task scheduling?

[bobbyhubbard]

Currently with tasks, we are having to manage the execution of their schedules external to CF. Additionally, we package those tasks with a parent application whose instance(s) runs 24/7/365. We prefer our architecture to be isolated by function and purpose...so if there is a task (something batchy) it should be deployed independently. This is in contrast to the current design of tasks which require a "parent" application. If I only run a task once a week, why should the parent app instance run that entire time listening? We would be forced to externally schedule the start and stop of the parent app AND separately the execution of the task. Yuk if I understand this correctly. Today we isolate the "batchy" functionality in its own application and use something like Spring Tasks to kick off the work. But again...it run 24/7/365 when it doesnt need to.

I am wondering if there has been any consideration for accepting an application push with a cron-style schedule? Essentially, the app is a task but it can be scheduled to spin up on its own. Once its done, the container is killed just like with a CF task today.

Maybe something like:
cf push mySimpleScheduledApp -p target/myApp.jar --schedule "0 * * * *"

Otherwise, are there any other recommendations or thoughts on approaching running batch/scheduled work loads on CF?

[cf-gitbot]

We have created an issue in Pivotal Tracker to manage this:

https://www.pivotaltracker.com/story/show/139966465

The labels on this github issue will be updated when the story is started.

[emalm]

Hi, @bobbyhubbard,

Thanks for asking about scheduling CF app tasks regularly on CF. I'm not personally aware of any solutions in the open-source community for running CF app tasks on a regular schedule, but that's certainly something for the CF teams to consider incorporating into the core of the platform. I also think the v3 Cloud Controller API will make it easier to manage tasks and processes separately within a single app, although @zrob and the rest of the CAPI team would be able to provide more detail on strategies for managing tasks independently of long-running processes. It does seem that one can run a task on an v2 app that's stopped, or on an app scaled to 0 instances, although I can't seem to start to push or start an app with 0 instances (perhaps as a safety guard).

Best,
Eric, CF Diego PM

[zrob]

@bobbyhubbard

I'm also not aware of any open source scheduling options.

Of note, you do not need to have the app running to run a task against it. So you can push an app, wait for it to stage, then stop the app. From this point you can run tasks.

Alternatively you can take a look at the V3 APIs which will allow you to generate droplets without ever starting an app. These APIs are experimental and will definitely be changing, but have recently been given backlog priority to GA in the near future.

[emalm]

Closing due to inactivity.