Idle timeout without client attached

[mrocklin]

Currently we have an idle_timeout= keyword. It's great! It stops people from leaving clusters on, potentially racking up needless cloud expenses.

I sometimes find myself wanting a different timeout when all clients have gone. For example I might want a one-hour timeout if I'm connected from my Jupyter session, but once I've disconnected I probably only want a five minute timeout (long enough for me to hit refresh on my notebook and reconnect).

With this in mind I'll propose a idle_timeout_no_clients= keyword and config value (better names welcome) that would, presumably, be set more aggressively.

cc @fjetter @jrbourbeau (maybe useful for coiled.run) and @ntabris (because I think he cares about these things).

[mercyo12]

@fjetter Hi, could I make a PR for this issue? Thanks!

[jacobtomlinson]

@mercyo12 please go ahead!

[fjetter]

@mercyo12 sure. If you need any pointers, either ask on this issue or open a draft PR with your work in progress.

Contributions are always welcome :)

[mercyo12]

hi, would we want to have both idle_timeout and idle_timeout_no_clients on at the same time, or if one is enabled the other isn't? thanks for the clarification!

[fjetter]

I think the intention here is to have two distinct values and it should be possible to set and enable both at the same time.

[crusaderky]

(ignore my previous post; I didn't consider that tasks will be forgotten as soon as the client leaves unless they're fire-and-forget)