Process Synchronization

Back to Operating Systems
Arjit Sharma
02 Mins

In modern computing, multiple processes run concurrently, often sharing resources. If these processes do not coordinate access properly, race conditions, data inconsistency, and deadlocks can occur. Process synchronization ensures orderly execution, preventing conflicts and maintaining system stability.

Why is Process Synchronization Important?

When multiple processes access shared resources without control, unpredictable behavior may occur:

  • Race Conditions – Two processes modifying shared data simultaneously, causing incorrect results.
  • Deadlocks – Processes get stuck, waiting indefinitely for resources locked by each other.
  • Inconsistent Data – Uncontrolled access leading to incorrect computations.

Example: In banking systems, two transactions modifying the same balance at the same time without synchronization could result in incorrect deductions or deposits.

General Structure of a Process

A process has multiple sections, but synchronization is critical in its critical section, where shared resources are modified.

Process Structure with Critical Section

while (true) {  
    // Entry Section (Checking if resource is available)  
    lock(resource);  
      
    // Critical Section (Shared resource accessed)  
    balance += 100; // Example: modifying shared data  
      
    // Exit Section (Releasing resource)  
    unlock(resource);  
      
    // Remainder Section (Other non-critical operations)  
}

In the above pseudocode, lock(resource) ensures that only one process modifies the balance at a time, preventing race conditions.

Criteria for Solving the Critical Section Problem

For an effective synchronization mechanism, it must satisfy:

  1. Mutual Exclusion – Only one process can be in the critical section at a time.
  2. Progress – If no process is in the critical section, others should be able to enter.
  3. Bounded Waiting – A process must eventually enter the critical section instead of waiting indefinitely.

Conclusion

Process synchronization is essential for ensuring correctness and stability when multiple processes operate on shared resources. By understanding how critical sections work and following synchronization criteria, developers can design robust and efficient concurrent systems—avoiding race conditions, deadlocks, and inconsistent data updates.

Next →