Tuesday 13 September 2011

Processes


Early computer system allowed any one program to be executed at a base, current days computer system allow multiple program to be loaded in memory and to be executed at the same time or step by step. This executing multiple programs is being resulted as process. A process is the unit of work in a modern time sharing system.
In modern system processing consist of processing a collection of processes. Operating system processes executing system code and a user processes executing user code all this process an executed simultaneously by the CPU.
Even on a single user system, such as Microsoft dos and Macintosh os, a user may be able to run several program at one time, a word processor, web browser and email package.
Even if the user can execute only one program at a time to support or control that particular program, an operating system executes several internal program activities. So, we can theses activities as a process. So, process can be defined as the program in execution compiling of an execution code is process.
A program by its self is not a process. A program is a passive entity such as content of a file or instruction code of particular files whereas process is an active entity. Which specify next instruction to execute and set if associated resources.
Operation on process
A process is usually sequential and consist of a sequence of action that take place one at a time when a set of process is running on a single cpu running the time slicing to multitask, then this is referred to as con current sequential processing or pseudo-parallel processing. If there is more than one CPU available, then processes may be running parallel.
The set of operation that a operating system can perform on process includes:-
a. Create a process
b. Destroy a process
c. Run a process
d. Suspend a process
e. Get process information
f. Set process information
Inter process communication:
Inter process communication is a facility provided by an operating system via which co-operating process can communicate with each other. This facility allows the process to co-operate and synchronize their active IPS. IPS is provided by co message system. IPS is useful in distributed system where the process communication depends on the different computer connected in the network.

0 comments:

Post a Comment