Concurrent Processes in Operating System

Concurrent processing is a computing model in which multiple processors execute instructions simultaneously for better performance. Concurrent means, which occurs when something else happens. The tasks are broken into sub-types, which are then assigned to different processors to perform simultaneously, sequentially instead, as they would have to be performed by one processor. Concurrent processing is sometimes synonymous with parallel processing.

The term real and virtual concurrency in concurrent processing:

  1. Multiprogramming Environment :
    In multiprogramming environment, there are multiple tasks shared by one processor. while a virtual concert can be achieved by the operating system, if the processor is allocated for each individual task, so that the virtual concept is visible if each task has a dedicated processor. The multilayer environment shown in figure.

  2. Multiprocessing Environment :
    In multiprocessing environment two or more processors are used with shared memory. Only one virtual address space is used, which is common for all processors. All tasks reside in shared memory. In this environment, concurrency is supported in the form of concurrently executing processors. The tasks executed on different processors are performed with each other through shared memory. The multiprocessing environment is shown in figure.

  3. Distributed Processing Environment :
    In a distributed processing environment, two or more computers are connected to each other by a communication network or high speed bus. There is no shared memory between the processors and each computer has its own local memory. Hence a distributed application consisting of concurrent tasks, which are distributed over network communication via messages. The distributed processing environment is shown in figure.

Don’t stop now and take your learning to the next level. Learn all the important concepts of Data Structures and Algorithms with the help of the most trusted course: DSA Self Paced. Become industry ready at a student-friendly price.

My Personal Notes arrow_drop_up

If you like GeeksforGeeks and would like to contribute, you can also write an article using or mail your article to See your article appearing on the GeeksforGeeks main page and help other Geeks.

Please Improve this article if you find anything incorrect by clicking on the "Improve Article" button below.