https://cppcon.org/
https://github.com/CppCon/CppCon2020
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C++20 and future C++ standards are expected to massively improve the ergonomics of asynchronous I/O within the C++ ecosystem. Yet, the vast majority of current operating systems (OSes) were designed without considering asynchronous I/O to be a first-class citizen. For example, Linux is only able to perform general-purpose asynchronous I/O since the recent addition of io_uring. Even with this new asynchronous mechanism in place, many I/O operations still have to fall back to a thread-based emulation within the kernel.

In this talk, we present Managarm, an OS designed around C++20 coroutines and the upcoming C++ sender/receiver model. Its main goal is to fully support asynchronous I/O through the entire system. All I/O operations are asynchronous in Managarm, with a single blocking system call to wait for their completion. The OS implements primitive asynchronous operations using (a variant of) the C++ sender/receiver model. These primitives comprise…