Async Rust: From Futures To Production Part1 chapter2 - "Output, poll(), Context, Waker" diagram requires more detail

[Migorithm]

The diagram simplifies the interplay between Executor and Reactor by lumping reactor with Resource(I/O) and Operating System.

While it'd be easier to understand for those who got to learn async rust for the first time, combining those three seem quite off.

I like to suggest the following diagram if it is not too complex

sequenceDiagram
    participant E as Executor
    participant F as Future (Task)
    participant OS as Operating System<br/>(e.g., epoll/kqueue)
    participant R as Reactor (Runtime)

    E->>F: Calls poll(cx)
    Note right of F: Future attempts operation
    F->>OS: Syscall (e.g., read TCP socket #4)
    OS-->>F: Returns Error: (Not Ready)
    
    F->>R: Registers: (Waker)

    
    F-->>E: Returns Poll::Pending
    Note left of E: Task is moved out<br/>of run queue
    

    E->>E: (Executor runs other tasks OR sleeps)
    R->>OS: epoll_wait() / Polls OS for events


    Note right of OS: (Sometime Later) New data arrives
    OS-->>R: Wakes Reactor: data is NOW READABLE
    Note over R: OS NOTIFIES REACTOR FIRST
    
    R->>R: Reactor finds Waker
    R->>E: Calls Waker::wake()
    Note right of E: Task is pushed back<br/>to Executor's run queue

    E->>F: Calls poll(cx) again
    Note right of F: Future attempts operation again
    F->>OS: Syscall (e.g., read TCP socket #4)
    OS-->>F: Success: Returns Data Buffer
    F-->>E: Returns Poll::Ready(Data)

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[atulkhare4096]

@Migorithm Seems like a reasonable suggestion. Can you please submit a PR?