mod_async_engine.so is a mod_async_engine
belonging to XTE Server for Citrix Access Suite
from Citrix Systems, Inc.
Non-system processes like mod_async_engine.so originate from software you installed on your system. Since most applications store data in your system's registry, it is likely that your registry has suffered fragmentation and accumulated invalid entries which can affect your PC's performance. It is recommended that you check your registry to identify slowdown issues.