#CriticalSectionProblem #ProcessSynchronization #operatingsystemlectures
Process Synchronization
Process Synchronization means sharing system resources by processes in a such a way that, Concurrent access to shared data is handled thereby minimizing the chance of inconsistent data. Maintaining data consistency demands mechanisms to ensure synchronized execution of cooperating processes.
Process Synchronization was introduced to handle problems that arose while multiple process executions. Some of the problems are discussed below.
Critical Section Problem
A Critical Section is a code segment that accesses shared variables and has to be executed as an atomic action. It means that in a group of cooperating processes, at a given point of time, only one process must be executing its critical section. If any other process also wants to execute its critical section, it must wait until the first one finishes.
Critical Section Problem
Solution to Critical Section Problem
A solution to the critical section problem must satisfy the following three conditions:
1. Mutual Exclusion
Out of a group of cooperating processes, only one process can be in its critical section at a given point of time.
2. Progress
If no process is in its critical section, and if one or more threads want to execute their critical section then any one of these threads must be allowed to get into its critical section.
3. Bounded Waiting
After a process makes a request for getting into its critical section, there is a limit for how many other processes can get into their critical section, before this process's request is granted. So after the limit is reached, system must grant the process permission to get into its critical section.