Proceskørsel

Proceskørsel is the execution of a process by an operating system. A process is a running instance of a program that has its own allocated resources, such as an address space, file handles and I/O privileges. Proceskørsel begins when the program is loaded into memory and the operating system moves the process from the ready queue to the running state.

During proceskørsel, the operating system maintains a process control block or similar data structure that holds information such as the process ID, current state, program counter, CPU registers, memory management details, open files, and accounting data. The system also manages resources and may preempt a running process to allow others to execute.

A central aspect of proceskørsel is scheduling. The OS scheduler decides which process runs next based on policies and priorities. To switch from one process to another, the system performs a context switch, saving the current CPU state and restoring the state of the next process. Processes can be in several states: new, ready, running, waiting (blocked on I/O or synchronization), and terminated.

In modern systems, proceskørsel involves multiple processes and often multiple threads, enabling concurrent execution and inter-process communication. Each process operates in its own virtual address space, providing isolation for stability and security; communication between processes uses mechanisms such as pipes, sockets, shared memory or signals.

Performance and reliability concerns in proceskørsel include issues like deadlock, starvation and scheduling fairness, especially on desktops, servers and embedded devices. Observability tools can display active processes, CPU usage and I/O activity to diagnose and optimize performance.