operating-systems

Definition

Process Control Block

A process control block (PCB) is a data structure storing the execution state and management information of a process, enabling suspension and later resumption.

Contents

Identification

PID, parent PID, and user ID.

Processor State

Context for resuming execution: program counter, general-purpose registers, stack pointer, and PSW.

Scheduling Information

Current process state and priority.

I/O Status

Open file descriptors, assigned devices, and pending I/O requests.

Memory Management

Pointers to page tables or segment tables defining the address space.

Location

Home in Kernel Space

The PCB resides in kernel space. All PCBs are indexed by the process table.