How to avoid task queueing (handling priority)

[gammazero]

How to avoid task queueing (handling priority)

[gammazero]

The priority queues I have generally seen use separate channels for different priorities, all feeding the same pool of goroutines. The highest priority channel is serviced until empty before servicing the next lower priority channel, and so on... I assume you doing something similar and feeding tasks to this worker pool.

The problem is that this workerpool is designed to be a non-blocking pool that you throw as many tasks at as you like without ever having to wait, even if that task is not immediately runnable. What you probably need is a blocking workerpool. So that when there are no available workers, the pool will not accept another task, and your tasks will stack up in the appropriate queues or channels.

To respond to your suggestion above, I do not think checking the number of active workers will be very reliable as that may become completely different immediately after the check. If that is still needed, then have the functions that are called increment and decrement a counter on entry and exit (or create a generic wrapper that does that).

A blocking implementation would be much simpler since most of the complexity in this workerpool arises from needing to handle queuing tasks when all workers are busy.

[radeksimko]

That is fair. I did eventually implement a custom worker pool with priority handling https://github.com/hashicorp/terraform-ls/blob/main/internal/terraform/module/module_loader.go

Your workerpool implementation did help us get things off the ground at the beginning, but it became clear later that we have a little more complex needs.

So with that in mind I'm going to close this issue.