operating-systems

Definition

Process Hierarchy

A process hierarchy refers to the parent-child relationship between processes. In many operating systems, every process (except the first system process) is created by another process, forming a tree-like structure.

Mechanism

  • Parent Process: A process that spawns one or more new processes.
  • Child Process: A new process created by a parent. It may inherit certain properties from the parent, such as open files or environment variables.

When a process is created, the operating system assigns it a unique identifier (PID) and records its relationship to its parent in the Process Table.

Significance

  • Resource Control: A parent process can often control or limit the resources used by its children.
  • Termination: In some systems, if a parent process is terminated, all its children are automatically terminated as well (cascading termination).
  • Parallel Tasks: A single logical task can be broken down into multiple parallel child processes to improve performance.