Here are some notes regarding PHP pThreads v3 that I have gathered:
-namespace: It does not understand namespaces.
-globals: It won't serialize GLOBALS at all! And will not register new ones.
-classes: It registers new classes okay.
-functions: Will not register ANY functions - they must all be in static classes. It does understand PHP native functions.
-consts: previous constants will transfer over. Don't make any new ones thou!
-pThreads only work in CLI - of course!
-If a thread crashes it automatically gets recreated.
-In order to 'force kill' any thread the parent must be killed. Or wait until all other tasks queued are complete and then terminate.
-Anything registered in a pThread does not seem to join the main thread ... which is good!
-pThreads seem to be very powerful on multi-core environments, just need to be careful on system resources... it can and will lock up a system if mis-configured.
-Finally, finding help for PHP pThreads is slim to none... especially v3!