https://github.com/caolan/async/blob/master/lib/internal/eachOfLimit.js https://github.com/caolan/async/blob/master/lib/internal/eac... - this is the code the a

https://github.com/caolan/async/blob/master/lib/internal/eachOfLimit.js https://github.com/caolan/async/blob/master/lib/internal/eac... - this is the code the async Node lib uses for every "(X)Limit" function to limit the number run at once.