Microkernels trace their roots back to Danish computer pioneer Per Brinch Hansen and his tenure in Danish computer company Regnecentralenwhere he led software development efforts for the RC 4000 computer. In 1967,

 ...

Early operating system kernels were rather small, partly because computer memory was limited. As the capability of computers grew, the

 ...

Inter-process communication (IPC) is any mechanism which allows separate processes to communicate with each other, usually by sending

 ...

Microkernel servers are essentially daemonprograms like any others, except that the kernel grants some of them privileges to interact with

 ...

As a microkernel must allow building arbitrary operating system services on top, it must provide some core functionality. At a minimum, this includes:

 ...

On most mainstream processors, obtaining a service is inherently more expensive in a microkernel-based system than a monolithic system. In the monolithic system, the

 ...

Device drivers frequently perform direct memory access(DMA), and therefore can write to arbitrary locations of physical memory, including various kernel data structures. Such drivers must therefore be trusted. It is a common misconception that this means that they

 ...