Question

I have a ruby script array when each element needs processing :

threads = []
elemets.each do  |element|
    threads.push(Thread.new{process(element)}}
end
threads.each { |aThread|  aThread.join }

how ever due to resource limitations, the script works in an optimal way if no more the four elements are processed at a time.

no I know I can dump the each loop and use a variable to count 4 elements and then wait
but is there a cooler ruby way to do it ?

Answer 1

You can enumerate in groups of 4 for an array:

>> [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12].each_slice(4) {|a| p a}
[1, 2, 3, 4]
[5, 6, 7, 8]
[9, 10, 11, 12]

So you can try something like

elements.each_slice(4) do | batch |
    batch.each do | element |
        threads.push(Thread.new{process(element)}}
        
    end
    (do stuff to check to see if the threads are done, otherwise wait )
end