Various freed multi-cores RTOS based Linux

Nowadays multi-cores operating system is widely used in real-time operating systems and embedded operating systems. Multi-cores operating system is stand for a set of system which is based on original system and design for some special purpose. It works as another kernel in the system and only response for several critical areas. These systems are smaller, but most of them will take care of process management which is an important and difficult part in operating system education. So it is more suitable for the operating system teaching. In this paper several open source multi-core operating systems will be introduced especially in process management.