Inter-Process Communication

operating-systems concurrency

Definition

Inter-Process Communication (IPC)

Inter-process communication provides mechanisms for processes to communicate and synchronise their actions. It is essential for coordinating cooperating processes in a multitasking environment.

Models

Shared Memory

A memory region is mapped into multiple processes’ address spaces. Processes exchange data by reading and writing this shared region.

Benefit: Maximum speed (memory access).
Challenge: Requires explicit mutual exclusion to prevent race conditions.

Message Passing

Processes exchange data via send/receive primitives, with kernel mediation.

Benefit: Easier to implement in distributed systems.
Challenge: Higher overhead due to kernel intervention per message.

Comparison

Feature	Shared Memory	Message Passing
Communication	Memory read/write	send/receive
Speed	High (memory speed)	Lower (system call overhead)
Synchronisation	Manual (semaphores, etc.)	Implicit in primitives
Suitability	Local communication	Distributed systems