Announcing Leapfrog, a faster concurrent HashMap

For a personal project I needed a concurrent HashMap, so thought I would port one of the fast C++ hashmaps to Rust., which I have called Leapfrog. The API is similar to the HashMap in the std library, but to improve concurrent performance it is slightly different in places.

I'm sure that there is a lot to improve, particularly in terms of usability since I have only used this for a handful of use cases, so it would be great to get some feedback, and to have this more thoroughly tested. I did implement the cuckoo tests, and they are passing, however, these don't cover nearly enough use cases.

On to performance ...

I have benchmarked this against other concurrent HashMap implementations and thus far the results are promising, at 16 CPU cores it's 2x the performance of DashMap. I forked the DashMap bechmarks to ensure fairness, and the link to the bechmarks are in the README and were done on a 3950X.

All feedback is welcome.