Kernel definition
A kernel is a program that lets users interface with their device’s hardware. Kernels are core components of operating systems (OS), managing processes, memory, I/O devices, and other critical tasks. Kernels are often insulated from user apps to avoid crashes.
Real kernel types
- Monolithic kernels use the same memory space for both user and kernel services, trading system stability and modularity for better performance.
- Microkernels use separate memory spaces for user services and kernel services. They are slower but more stable and easier to modify.
- Hybrid kernels run non-essential kernel services in the kernel memory space while keeping essential services in the user space.
- Nanokernels are compact kernels that support a nanosecond clock resolution.
- Exokernels are a complex new type of kernel designed for application-specific resource allocation.
