Monoio seems to be the most performant runtime, and actually easy to use - we have decided to go with "bleeding edge" approach, as it will still take at least a few months to implement io_uring and other optimizations, as we'll have to rewrite some of the core parts and most likely shift towards thread-per-core architecture.
For what it’s worth I don’t believe it meaningfully outperforms glommio. There are some spots where it outperforms glommio but that’s just a missing optimization that could be added. The biggest advantage monoio really has is that it currently has support for other platforms.
Not saying it’s the wrong choice, just highlighting the trade offs.
I’m not sure what you mean by io_uring as glommio/monoio should be hiding the io_uring details behind the runtime.
Of course, they hide the details behind io_uring, it's just that monoio seemed even easier to work with. It's not set in stone, though, actually there are new runtimes being developed as we speak, for example mfio - we'll see what will be our final choice, but we've decided to start with monoio.
Speaking of the other platforms, having the fallback to epoll or kqueue (they've even announced some Windows integration) is nice to have, however, at some point we might just purely focus on Linux development anyway (io_uring only), if there'd be any issues e.g. when it comes to the code design to provide the compatibility across multiple OS.
