[mleonhard]

The problem is that the system is RAM-constrained but the work scheduler doesn't use a RAM pressure signal.

We could solve this with a crate that rate-limits new tasks based on heap usage.

We could build this into the runtime and make it apply to all task spawns. That could be problematic since any spawn could block.

It would probably be better to make it opt-in and less granular, releasing groups of tasks at a time.