Unformatted text preview: ter system is used to simultaneously handle several
applications, there may be many, possibly conflicting, requests for resources. In
such a situation, the operating system must decide which requests are allocated
resources to operate the computer system efficiently and fairly (providing due
attention to all users). The efficient and fair sharing of resources among users
and/or programs is a key goal of most operating systems.
Main Functions of an Operating System
We saw that an operating system provides certain services to programs and to the
users of those programs. The; specific services provided will, of course, differ
from one operating system to another, but there are some common types of
functions that we can identify. The main functions provided by most operating
systems of today are as follows: 1.
Process Management. A process is a program in execution. During
execution, a process needs certain resources such as CPU time, memory space,
files, and I/O devices. At a particular instance of time, a computer "system
normally consists of a collection of processes. The process management module
of an operating system takes care of the creation and deletion of processes,
scheduling of various system resources to the different processes requesting them,
and providing mechanisms for synchronization and communication among
2. Memory Management. To execute a program, it must be loaded, together with
the data it accesses, in the main memory (at least partially). To improve CPU
utilization and to provide better responses time to its users, a computer system
normally keeps several programs in main memory. The memory management
module of an operating system takes care of the allocation and deal location of
memory space to the various programs in need of this resource.
3. File Management. All computer systems are used for storage, retrieval and
sharing of information. A computer normally stores such information in units
called files. Processes can read information from files and can create new files
for storing newly generated information. Information stored ii files is made
persistent by storing them on a secondary storage media s...
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This document was uploaded on 04/07/2014.
- Spring '14