Priority threshold

[j-woz]

Need a feature to suspend release of prioritized tasks until a user-provided queue size (or time) is reached, allowing for prioritization to happen.

Start with TURBINE_PRIORITY_THRESHOLD=10

meaning: don't release prioritized tasks until 10 are in the queue.

CC @jozik @ncollier

[jozik]

My sense is that the queue length won't help in the use cases we were thinking about, but a combination of the following two:

• Priority threshold: defines a priority value under which tasks are accumulated until a (below defined) idle time is reached
• Idle time: time measured from last accumulation of under priority threshold tasks, such that if tasks are not being accumulated for a while, they will be sorted by priority and sent to workers

would. Without the priority threshold value (i.e., one that says what's the threshold of priority values for tasks under which they will be accumulated), we'd be tracking tasks that don't need to be accounted for, so it would be particularly hard to assign a meaningful queue length. Also, our use cases indicated that providing a task accumulation idle time should be simple and intuitive enough to specify.

[j-woz]

That makes sense.