Re:Why asynchronous Rust doesn't work
by pornel on Wednesday March 10, 2021 @08:38AM
(#26411049)
Things that are easier with Rust's async:
• Timeouts and cancellation. Rust's async code can be aborted from the outside (with correct cancellation and cleanup of everything in progress). OTOH if you run imperative blocking code, you need every blocking function to cooperate.
• Full utilization of CPU and I/O in workloads that mix both. Async executor balances threadpools/polling queues for these automatically. OTOH if you just use regular blocking calls with no state machines/continuations, it will be hard to separate these two. A single mixed-use threadpool will oscillate between I/O-bound threads and underutilizing CPU, and CPU-bound threads and idling I/O.
• Timeouts and cancellation. Rust's async code can be aborted from the outside (with correct cancellation and cleanup of everything in progress). OTOH if you run imperative blocking code, you need every blocking function to cooperate.
• Full utilization of CPU and I/O in workloads that mix both. Async executor balances threadpools/polling queues for these automatically. OTOH if you just use regular blocking calls with no state machines/continuations, it will be hard to separate these two. A single mixed-use threadpool will oscillate between I/O-bound threads and underutilizing CPU, and CPU-bound threads and idling I/O.