Feature request: runtime-tokio-singlethreaded

[vi]

Choose one: feature request.

Expected Behavior

One of runtimes from the list to choose provies fully single-threaded (no clone syscall) application (unless I manually call std::thread::spawn, of course).

Current Behavior

There seems to be no such thing in the list.

Possible Solution

Add a runtime based on tokio::runtime::current_thread.

Context

Reasons to be singlethreaded:

• To economize OS resources when not doing highload.
• To use non-threadsafe libraries with Rc<RefCell>s inside
• To debug applications more easily before going multithreaded
• To use async in environment without OS threads
• To embed code into larger apps which may become broken if the code suddenly spawns a thread
• To speed up by removing futex (synchronisation) cost on single core systems.

[yoshuawuyts]

@vi thanks for filing this. Implemented in #3, and released as runtime-tokio@0.3.0-alpha.2 :tada: