Async limit

[oxinabox]

It is reasonable to use a semaphore for this, as described here for threads:

Control number of threads

Semaphore You can use what ever threading solution you want. (Including Threads.@threads ) plus a Base.Semaphore to control number of threads active at a time. Something like using Threads sem = Base.Semaphore(2) # at most 2 at a time Threads.@threads for ii in 1:100 Base.acquire(sem) println(threadid()) Base.release(sem) end This will ensure only 2 threads are doing anything at a time. THough which two may change (and in the case of Threads.@thread will because of how it all…

I have also seen a Channel used as a adhoc semaphore.
Which is marginally faster since it is not having to take out locks etc.
but probably not worth the loss of clarity for code.
Plus using a semaphore frees you to change from tasks to threads later.
(threads are just tasks without the sticky bit set)