Process Communication in Operating System

Processes executing concurrently in an operating system can be classified as independent processes or cooperating processes. An independent process cannot affect or be affected by other processes in the system and does not share data with any other process. A cooperating process can affect or be affected by other processes and shares data with them.

Why Process Cooperation is Important

Operating systems provide environments that support process cooperation for several key reasons:

• Information sharing − Multiple users may need concurrent access to the same information, such as shared files or databases.

• Computation speedup − Tasks can be divided into subtasks that execute in parallel, reducing overall execution time.

• Modularity − Systems can be built with separate processes or threads handling different functions, making the system easier to design and maintain.

• Convenience − Users can perform multiple activities simultaneously, such as editing documents, listening to music, and compiling programs.

Inter-Process Communication (IPC) Models

Cooperating processes require an Inter-Process Communication (IPC) mechanism to exchange data and information. There are two fundamental IPC models:

Shared Memory Model

In the shared memory model, cooperating processes establish a region of memory that is shared among them. Processes exchange information by reading and writing data to this shared region. Once the shared memory is set up, all subsequent accesses are treated as routine memory accesses with no kernel assistance required.

Message Passing Model

In the message passing model, communication occurs through messages exchanged between cooperating processes. The operating system kernel facilitates this communication by providing mechanisms for sending and receiving messages.

Comparison of IPC Models

Conclusion

Process communication is essential for cooperating processes to share information and coordinate activities. Both shared memory and message passing models have their advantages, with shared memory being faster for large data transfers and message passing being more suitable for distributed systems and smaller data exchanges.