Pulp

Motivation¶

Dependency solving for multiple repositories (which implies copy to multiple target repositories) requires the ability to lock on multiple resources.
Without this feature, changes to a repo might not be deterministic.

Solution¶

• Change uniqueness constraint on the ReservedResource model, from task_id to (task_id, resource_id).
• For multi-lock task choose a worker if only 0 or 1 workers have a lock for any of the resources from a multi-lock task, otherwise wait.
• release all the locks for the task when it's complete.
• document the worst case scenario (N-2 works can be idle until there is only one worker being busy)

the pulp3 patch adding multi-locking support https://github.com/pulp/pulpcore/commit/ff0739e9a9fe4d3c0762e498ae59ec756d02fb71