Sub-Process VS send/receive message event

Question

A sub-process need to inform parent with details(CDT) , the parent process can call the child-process in asynchronous manner since parent process as some parallel activities. For this i have few approach : 
 
 Parent will split the instances into two, one will the call sub-process node in synchronous manner. Another instances will carry other parallel task

Another approach , i will not the split the parent instances , just call the process asynchronously (Start-process node). which will in turn create an instances in child process. Once child process finishes it will inform the parent via "send message event" from child

Which implementation will have lesser impact on performance......

Mike Schmitt · Answer

Generally I'd rather implement something closer to your first approach (split process flow with AND node, call subprocess synchronously, get data from it when done), because while the Send Message approach can work, it can be a nightmare in terms of management, debugging and upkeep. I don't expect either approach would be all that different in terms of performance unless the subprocess is doing something unusually process-intensive.