I have recently set up and activated 4 processes using the process builder to send email reminders (alerts) when records are past the due date. I needed 4 because there are 4 emails send at different times so needed 4 different schedules for the same criteria. One of these processes has 5 criteria nodes the rest have 3. After activation my test class execution time went from ~ 20 minutes to over 60. I tracked it to workflow where I found that a test class that takes 9 seconds in sandbox takes 85 in production with the debug log indicating 35 seconds for each workflow execution. There are several dozen other workflow rules but these run really fast and are just as complicated as the criteria on the process if not more so. The test class inserts 200 records that the process is based on then inserts 200 related records that update the original 200 via a trigger so the process is kicked off twice. (create/update)
My question is Are Process Builder processes really that heavy on system resources? or do I have a setting set up wrong somewhere.