So I've been testing the performance a bit, varying e.g.

• 1:1, 16:1, 64:1 producer : consumer ratio
• normal/lifo/priority queue etc
• asyncio/uvloop event loop
• async -> async, async -> sync, sync -> sync
• (probably more)

I found that, janus queues are ~5x slower in sync->sync, ~9x slower in sync->async, and ~15x slower in async->async. This is pretty much consistent across all parameter sets.

This confirmed my suspicion that the performance gain of parallel computation is often less than the cost of using e.g. threading.Lock a lot (the GIL certainly doesn't help either).

Right now, I can imagine that many users have incorrect expectations of janus. To avoid this, you could add an example that shows how janus can outperform single-threaded asyncio, by employing multiple threads. Additionally, a caveat about janus' performance would be helpful.