Easy pthreads Pools
The final solution !!
Since the first version of pthreads, PHP has had the ability to initialize Worker threads for users. Onto those Worker threads are stacked objects of class Stackable for execution concurrently.
The objects stacked onto workers do not have their reference counts changed, pthreads forces the user to maintain the reference counts in userland, for the extremely good reason that this enables the programmer to keep control of memory usage; and so, execute indefinitely.
This is the cause of much heartache for newcomers to pthreads; if you do not maintain references properly you will, definitely, experience segmentation faults.