Operating System - Multiprocessor System

In an Operating System (OS), a multiprocessor system refers to a computer system with two or more processors (CPUs) that share the same physical memory and communicate with each other through the operating system. These systems are also known as parallel systems or tightly coupled systems.

Multiprocessor System

A system with multiple CPUs that work together to execute multiple processes simultaneously.

All CPUs access a common main memory, allowing for faster communication and coordination.

Symmetric vs. Asymmetric Multiprocessing

  • Symmetric Multiprocessing (SMP):

    • All processors are equal.

    • Each processor runs a copy of the OS.

    • Tasks are evenly divided among processors.

  • Asymmetric Multiprocessing (AMP):

    • One master processor controls the system.

    • Others perform tasks assigned by the master.

    • Less common in modern systems.

 Benefits of Multiprocessor Systems

Benefit Description
Increased Throughput Multiple processors can perform more tasks in parallel.
Faster Processing Tasks can be divided and processed simultaneously.
Greater Reliability If one CPU fails, others can continue (fault tolerance).
Efficient Resource Sharing CPUs share memory and I/O, reducing hardware duplication.

 How the OS Manages Multiprocessors

  • Task Scheduling: The OS must efficiently distribute tasks across CPUs.

  • Process Synchronization: Ensures processes do not interfere with each other when accessing shared resources.

  • Load Balancing: Evenly distributes work to avoid some CPUs being idle.

  • Concurrency Control: Handles multiple threads or processes executing at the same time.