Limit concurrency with Mutex?

[dirtyhairy]

Limit concurrency with Mutex?

[DirtyHairy]

Published.

[DirtyHairy]

Hi Joe!

Thanks alot for the kind words 😏 I like the idea of adding a semaphore implementation. I've been planning on overhauling the library for some time now anyway, and extending it to a semaphore with Mutex as a special case on top of it sounds like a good plan. If you can wait for this for another week or so, I'll go for it.

Cheers
-Christian

[joerick]

Thanks! I also came across this - https://github.com/notenoughneon/await-semaphore - but it seems more Node-centric. I'm currently using an adapted version of it in my app as I needed to get something working for now. Could be useful for inspiration!

[DirtyHairy]

Done. I still have to update the documentation and do a release, but I have overhauled the library and added a Semaphore and a corresponding SemaphoreInterface.

A semaphore starts out with a positive definite value that is decremented each time it is locked and incremented on release. Once it has reached zero acquire will block until it has been incremented again. The API is pretty similar to Mutex --- acquire will return a tuple of the current semaphore value and the release callback, and runExclusive will pass on the current semaphore value to the callback. By definition, the values returned will be within 1 .. N where N is the initial value of the semaphore.

I'll do a proper release with updated documentation in the next days, but if you feel adventurous... 😏

[joerick]

Nice! One note - I think for a semaphore runExclusive could be the wrong name - it's not exclusively running. Maybe just run would be okay?

[DirtyHairy]

I had the same inclination. However I‘d like to keep the interface consistent between Mutex and Semaphore, and renaming the method on Mutex is not an option as it would break compatibility with existing code. The same issue exists with isLocked.

Besides, a semaphore is usually used to acquire exclusive access to one instance of a limited resource, so the naming might not be entirely bad on a second glance 😏