Feature Request: Add an async interface

[junderw]

It would be nice to wrap rocksdb in an async interface so that it could be used in an async context without blocking the async worker threads.

[zaidoon1]

I think this is relevant to you #687, specifically #687 (comment)

I've had the same problem and ended up using spawn_blocking for all rocksdb operations so that I don't block the async runtime. I'm still new to rust but I think that's the best/only option right now?

[junderw]

I think this issue is even more relevant. facebook/rocksdb#11017

Since this Rust library is only a wrapper around the C++ library, it would be hard to setup something using mio etc. unless the underlying library can make use of epoll and kqueue etc.

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ended up using spawn_blocking for all rocksdb operations so that I don't block the async runtime.

There is also block_in_place which is less restrictive and more performant in most cases.