Don't do ... what, exactly? The RFD answers this more precisely and provides suggestions for alternatives. But it's not very simple because the things that can cause this are all common patterns individually and it's only the confluence (which can be spread across layers of the program) that introduces this problem. In our case, it wasn't a Mutex, but an mpsc channel (that was working correctly! it just got very briefly saturated) and it was 3-4 modules lower in the stack than the code with the `tokio::select!` that induced this.