Process Synchronization
In computing, process synchronization is the coordination of the activities of multiple processes in order to ensure that the processes are working as expected. This coordination of processes is necessary for a successful computer system as it prevents conflicts or races between processes. Process synchronization also helps maximize the throughput of a system as all processes must wait for one another to finish in order for the entire system to finish.
Process synchronization has many implications on the development of software and systems. When more than one process needs to access a shared resource, synchronization of the processes is paramount. Without synchronization, each process could attempt to access the shared resource simultaneously, creating a race condition that could corrupt the resource. Examples of synchronization problems may include multiple processes accessing a shared file or printer, or a program with multiple threads attempting to access a shared variable. In each case, a synchronization technique must be employed to prevent concurrency problems. Process synchronization techniques guarantee atomicity and can be used to prevent concurrent access problem mentioned before.
One example of synchronization techniques is the use of semaphores. Semaphores are an abstract data type that provides a signaling mechanism between the processes in the system. They can be used to achieve synchronization by allowing multiple processes to wait on a value before proceeding to execute. Another example of synchronization techniques is the use of locks, which allow multiple processes to access a critical region of code without interfering with one another. This is accomplished by forcing the other processes to wait until the lock is released before they can enter the critical region and access the resource.
A third popular technique for process synchronization is the use of monitors. Monitors are used to control and manage concurrency by providing an abstracted synchronization primitive. The effects of a monitor are that threads within the same monitor can access shared data without interference from other threads. This effectively eliminates the problems caused by race conditions and explains why monitors are a preferred synchronization primitive.
Finally, another popular technique for process synchronization is the use of transactional memory. Transactional memory is a constraint based system that allows multiple threads to access shared memory variables atomically. This means that the system guarantees that all operations will be performed in a consistent and predictable order, no matter how many threads are accessing the same variables. Transactional memory can be used for both parallel programming (when multiple threads need to access the same variables) and for lock-free programming (when a thread needs to access a shared variable without interference from other threads).
Process synchronization is an important concept in computing because it prevents conflicts and race conditions while also maximizing throughput in a computer system. Without synchronization, it would be difficult to prevent concurrent access problems, meaning that the whole system may become corrupted and unreliable. All forms of synchronization are necessary for a successful system, however the best option will depend on the particular circumstances in which they are used.
