> linux for example doesn't have true IO async API
io_uring has been around for a few years at this point, with vulnerabilities having been fixed to the point that it's fit for broadband usage.
In this discussion people claim io_uring is not real async IO, but just another kernel level threadpool: https://news.ycombinator.com/item?id=38919659
except now you need to prove somehow that all 100 libs in your project support virtual threads.
> Virtual threads improve throughput because the moment a task is waiting for anything like IO, the thread is able to service any other task in the queue.
from reading similar discussions, linux for example doesn't have true IO async API, you just push lock of Java thread to lock of thread in the kernel