Hi May I ask the design tradeoff for channel, why it's mpsc, spsc should also work nicely, does it against single writer principle?
A multi-producer channel is more powerful than a single-producer channel.
When the sender is not cloned it does use an efficient SPSC implementation underneath I believe, and it can dynamically switch implementations on the fly.
If you're after efficiency, then you should use:
Despite being mpmc, it's way faster than std in all cases, even when used with just one producer and one consumer.