Thread and process

Question

Can anyone explain thread and process in .net?

Anuja Pawar · Answer

Process: An executing instance of a program is called a process. Some operating systems use the term 'task' to refer to a program that is being executed. A process is always stored in the main memory also termed as the primary memory or random access memory. Therefore a process is termed as an active entity. It disappears if the machine is rebooted. Several process may be associated with a same program. On a multiprocessor system multiple processes can be executed in parallel. On a uni-processor system though true parallelism is not achieved a process scheduling algorithm is applied and the processor is scheduled to execute each process one at a time yielding an illusion of concurrency. Example: Executing multiple instances of the 'Calculator' program. Each of the instances are termed as a process. Thread: A thread is a subset of the process. It is termed as a 'lightweight process' since it is similar to a real process but executes within the context of a process and shares the same resources allotted to the process by the kernel (See kquest.co.cc/2010/03/operating-system for more info on the term 'kernel'). Usually a process has only one thread of control – one set of machine instructions executing at a time. A process may also be made up of multiple threads of execution that execute instructions concurrently. Multiple threads of control can exploit the true parallelism possible on multiprocessor systems. On a uni-processor system a thread scheduling algorithm is applied and the processor is scheduled to run each thread one at a time. All the threads running within a process share the same address space file descriptor stack and other process related attributes. Since the threads of a process share the same memory synchronizing the access to the shared data withing the process gains unprecedented importance.

Satyapriya Nayak · Answer

Hi Sonakshi A process is a collection of virtual memory space code data and system resources. A thread is code that is to be serially executed within a process. A processor executes threads not processes so each application has at least one process and a process always has at least one thread of execution known as the primary thread. A process can have multiple threads in addition to the primary thread. Prior to the introduction of multiple threads of execution applications were all designed to run on a single thread of execution. When a thread begins to execute it continues until it is killed or until it is interrupted by a thread with higher priority (by a user action or the kernel's thread scheduler). Each thread can run separate sections of code or multiple threads can execute the same section of code. Threads executing the same block of code maintain separate stacks. Each thread in a process shares that process's global variables and resources. Refer the below link http://www.codeproject.com/KB/ threads/IPC.aspx Thanks