Scheduler is the most critical system of an operating system. In order to optimize the use of processors, different scheduling algorithms are used. When the system has several processes to be performed, it must have an ability to make decisions on what process to run at a given time interval. This strategy should take into account the concepts to maximize throughput while minimizing latency and also avoiding process hunger etc. Many scheduling algorithms are widely used nowadays.
Planning is the basic concept of the design of the operating system. In multiprogramming, the processes that are loaded into the main memory strive for the resources of the processor time es. During execution of a process, other processes to wait to occur any event or for an I / O to be performed. regulates planning the execution of these processes ie what process will run and which process will wait. The objectives that must be met by the scheduling algorithm include efficient use of processor time, throughput and turnaround, responsiveness and fairness. OS can be categorically divided into three different types of programming: the long-term planning that is, the short-term and medium-term planning programming.
Have multi-user systems can simultaneously perform a hundred applications, but these systems provide some isolation between users. However, the absence of isolation can lead some users to perform poorly or intentional or unintentional DoS (Denial of Service). In recent cluster computing, these problems can be easily avoided by using the concept of jobs and scheduler activity. This refers the job until the resources are available and program after the availability of all possible resources.
Categories:
An operating system may be the most well known software that you run on our personal computer, is the one that takes care of pretty much everything on your computer, while almost all computer systems that we have seen are actually a 'type' of the operating system to perform exactly the same functions. OS could be branched in a number of types too. Within the broad group, there are many types of operating system that are mainly classified according to the type of computer systems that control and also the type of programs that claim.
Depending on the nature of the domain, operating system can be broken down into some of the following types.
1. Real-time OS:
A real-time operating system (commonly known as RTOS) is specifically designed to serve the application requests in real time. The main feature of a real time operating system is its consistency level that it takes to accept and finish any task of the associated applications.
2. Embedded OS:
Embedded systems are systems commonly limited resources and response time is a requirement extremely significant. Since the most important parts of embedded real-time OS, the scheduling algorithms are presented to improve the real-time embedded systems. The most existing real-time scheduling algorithms are based on processes with little consideration on system resources.
3. Network OS:
The network operating system (NOS) is the software that is installed on a server and it allows the data management servers, groups, users, applications, security, and many other network activities. The network operating system is designed to allow you to share files and access to the printer among multiple computers in a network, usually a local area network (LAN), private network or other networks.
4. Mobile operating system:
A mobile operating system (mobile OS) is designed to control a smartphone , tablets, PDAs, or other mobile device. Modern mobile operating system combining the features of a personal computer operating system with touch screen, mobile phone, Bluetooth, WiFi, GPS mobile navigation, camera, voice recognition camera, voice recorder, music player, Near Field Communication and personal digital assistants (PDAs), and many other features.
In 06, Windows Phone, Android, Bada and IOS have not yet been developed, and just 64 million smartphones were then sold. Today, nearly 10 times the number of smartphones are already sold and the best mobile operating system was promoted as a "smartphone" by the market share which includes BlackBerry, Android, Symbian, Apple, iOS, MeeGo, Bada and Windows Phone.
5. Distributed OS:
A distributed operating system is the logical combination of the OS software on a set of independent computing nodes in the network, connected, communicating, and physically distinct. The collection of management components and micro-kernel work together. They provide support for the goal of integrating various system resources and processing capabilities into an effective and established system.
In this article, was performed a review of the study of different operating system. The ease of techniques that are used supports the claim that the scheduling algorithms provide easy to use, highly flexible and the most optimal solution to any problem related to the ordinary work sequencing. This work can be extended to consider, examine and evaluate the dynamic scheduling algorithms and in particular domain sequencing work problems.
0 Komentar