Task option: only one running task at a time

Would this then be per user or across the whole application?

Across the application. I figure you would use this tickbox for processes that make large calculations or predictions where you want a max of 1 of these tasks to run. 

@Erwin Ekkel I disagree. The application / code / procedure should be able to have multiple running instances. If this is causing problems, this should be resolved programatically. How would applications with multiple users work? You, as a user, need to guess if one of your 1,000 colleagues is running the same task?

I think if you have a situation like this, you should use some kind of queueing mechanism instead and have a single background thread (systemflow?) handle running the actual logic.

I totally agree with @Robert Jan de Nie, this is potentially creating a mess. Having asynchronous tasks introduces complexity to the software you'd probably want to prevent. And is also very unclear to end users. Having problems with asynchronous tasks is in my opinion an exception and should not be standardized, so I would like to downvote this idea 😉.

In our current application we have some “long” running tasks which we eventually want to run asynchronous, but preferrably not.

I've explained it a bit over here (last post): 

I think it's better to look towards what's causing the issues with asynchronous tasks, is it maybe bad UX?

Topic closed, I retract the wish for now.