tokio-concurrency

Fan-out/fan-in patterns distribute work across multiple Tokio workers and collect results. Spawn tasks that process items in parallel, then join or channel results back to coordinate completion and aggregate outcomes.

Pipeline processing chains multiple async stages using channels for inter-stage communication. Each stage receives input, processes it, and forwards output to the next, enabling backpressure control and staged task distribution.

Rate limiting in Tokio uses token bucket or leaky bucket approaches to throttle operation frequency. Implement via channels or semaphores to prevent overwhelming downstream systems and manage backpressure.

Coordinated shutdown with CancellationToken enables hierarchical cancellation across dependent tasks. Propagate tokens through the task tree so parent cancellation triggers cleanup in all child tasks simultaneously.

Parallel task execution with join in Tokio spawns multiple tasks concurrently and blocks until all finish. Use tokio::join! or task handles to await completion and collect results from parallel async operations.

Use advanced patterns like fan-out/fan-in and pipelines when handling high-concurrency workloads requiring coordinated task distribution, backpressure control, or multi-stage processing that basic spawning cannot efficiently orchestrate.