Await multiple async functions in python

Question

Awaiting for multiple async functions is not really working asynchronously,for example,I am expecting below code to run in ~6 seconds, but it is running like synchronous code and executing in ~10 seconds. But when I tried it in asyncio.gather, it is executing in ~6 seconds.

Can someone explain why is this so?

 #Not working concurrently
 async def async_sleep(n):
    await asyncio.sleep(n+2)
    await asyncio.sleep(n)
start_time = time.time()
asyncio.run(async_sleep(4))
end_time = time.time()
print(end_time-start_time)

#Working concurrently 
async def async_sleep(n):
    await asyncio.gather(asyncio.sleep(n+2),
                    asyncio.sleep(n))

Answer 1

Can someone explain why [gather is faster than consecutive awaits]?

That is by design: await x means "do not proceed with this coroutine until x is complete." If you place two awaits one after the other, they will naturally execute sequentially. If you want parallel execution, you need to create tasks and wait for them to finish, or use asyncio.gather which will do it for you.