Proposal: Get Queue information

[TomC]

One thing I have always wanted in Cylc was to be able to get more information about the user-defined queues within Cylc. When tasks belong to multiple namepsaces, and both are assigned to different queues, a user may not understand which queue is being used. I think warnings may exist to try to highlight this, but, I thought being able to do a CLI command to

1. Obtain a list of which task namespaces belong to which queues
2. Query a queue for task and see which queue it belongs to
3. Obtain information about the queue state
   • Number of tasks active in queue
   • Number of tasks waiting on queue to find space for them
   • For any given queue, what tasks are active
   • For any given queue, what tasks are waiting

Then, in the WUI (and TUI?), have a view or frame which can show this sort of information too.

Would this be possible and would others find it useful being able to see more detail about the internal queue states?

[hilary.j.oliver]

Yes, I think that’s a good idea.

From a comment in the code:

  Each task can belong to one queue only.

  If a task is assigned to multiple queues the last assignment takes
  precedence. The "default" queue contains tasks not in another queue

Somewhat surprisingly, it looks like we don’t have any validation warnings or user documentation on the result of assigning the same task to multiple queues. I’ll post an issue to address that.

Queue config validation and documentation

[hilary.j.oliver]

New issue posted for the proposal too: Provide queue information on request? · Issue #6824 · cylc/cylc-flow · GitHub

[oliver.sanders]

We have some ideas in the pipes…

1. Represent queues as/like xtriggers (?):

2. Queue view for the GUI.