SPSCQueue.h VS junction

A triple buffer is a good choice if all you want is polling the latest data at any given time, and you want to avoid mutexes altogether. If you want each piece of data to be delivered exactly once, you can use a queue (bounded or "unlimited" though the latter doesn't supply backpressure which I hear causes problems). SPSC lock-free bounded queues are dead simple to write, and can be tuned for higher throughput even with contention (https://github.com/rigtorp/SPSCQueue claims to be nice, and I haven't had issues working with it aside from having to peek and pop separately, but it's C++, and not a misuse-proof API since it doesn't use the "handles" idea I talked about, and you can push/read/pop from the wrong thread). If you want the reader to poll/WaitForMultipleObjects until the queue has items, that has to be done separately from the SPSC.

And mutexes make a lot of things easier... and introduces "oops wrong mutex!" (Rust solves it) and deadlock (Rust doesn't solve it).

junction has a very impressive performance benchmark here. Initially it worked for my application, but I ran into some issues: Only raw pointers are supported as either keys or values. This means I am responsible for memory management and it was a pain. junction's required dependency "turf" causes linker errors when compiling with -fsanitize=address because there are symbol name collisions. Every thread that accesses the hash map must periodically call an update function or memory will be leaked. No commits in over three years, GitHub issues aren't getting any attention. The author said it's experimental and he doesn't want it to become more popular