Are the async tasks terminated after the return?

In my handler, I send some time-consuming tasks to an async function, then return the result to API Gateway, coz I don’t have to await the result of the async tasks.

However, I found that the async tasks will not be completed but stop running after the return.

What’s the problem? Must I create a queue to run them in another lambda invocation?

No they aren’t necessarily terminated. And it’s not a good idea to rely on this. A queue or a step function is a better way to handle this.