Coroutine

As we delve into the all-important topic of coroutines, we'll revisit some of the concepts discussed earlier to setup the context for our discussion around coroutines.

Cooperative Multitasking

Folks familiar with multithreading will know that a system achieves concurrency by context switching threads for CPU time. Threads can be taken off of the CPU if they engage in an I/O call or exhaust their time slice. The OS prempts a thread forcing it to give up the use of the CPU. Cooperative Multitasking, on the other hand, takes a different approach in which the running process voluntarily gives up the CPU to other processes. A process may do so when it is logically blocked, say while waiting for user input or when it has initiated a network request and will be idle for a while.

The process scheduler relies on the processes to cooperate amongst themselves while using the CPU and is the reason why this paradigm of multitasking is called cooperative multitasking or non-preemptive multitasking.

Coroutines in Python enable cooperative multitasking. The onus of scheduling processes in ...