Question: Meaning of memory leak when using async/await

[milad2golnia]

You are giving a warning to don't use the async/await syntax inside the AsyncTask:

Note that in order to avoid memory leaks, it is recommended to use promise chains instead of async/await inside task definition.

I watched the video you mentioned but I still couldn't figure it out what you are concerning about? I think this warning is not the case when I'm scheduling a single job (or scheduling some few - less than 10 - jobs). So are you warning about executing many multiple tasks which are using async/await syntax simultaneously because each await is creating 3 promises in heap memory? It is appreciated if you give an example of how using async/await could results in memory leak. Personally, I prefer to use async/await syntax always because it is more readable and that's why I'm curious about your warning.

[olsonpm]

I also don't understand the warning - it feels wrong as I consider myself pretty knowledgeable in promises. Async/await is no different from promises and thus should behave the same regarding memory leaks

[kibertoad]

Please watch https://www.youtube.com/watch?v=XV-u_Ow47s0 It explains why callback and async functions shouldn't be mixed. You can do that as long as you handle rejections properly, of course.

[olsonpm]

I'm sorry but I'm not going to sit through a 30 minute video regarding a concept that I understand very well. Videos are a slow form of communication compared to written material. If you have a timestamp or a post somewhere that explains your point better then I'll take a look and discuss, but it sounds like you're warning against improper use of promises rather than async/await

[kibertoad]

It's not about async/await per se, but about mixing callbacks and promises. async/await is perfectly fine here as long as you are handling unhandled rejections properly, which you don't get for free when creating promises in a callback (it will not bubble up to your global error handler). toad-scheduler does its best not to crash your app if your promise throws (see https://github.com/kibertoad/toad-scheduler/blob/main/lib/common/AsyncTask.ts), but it's much better when there is explicit error handling on your end.

[olsonpm]

gotcha - thanks much

[milad2golnia]

You can do that as long as you handle rejections properly, of course.

So you should give a warning about unhandled rejections not memory leak, Am I right? Because unhandled rejections results in crash and not memory leak.