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Operating System

CPU Scheduling Algorithm ?

CPU Scheduling Algorithm:- CPU Scheduling Algorithm is given below:- First-Come First-Served Scheduling:- The process which comes first is executed first. The simplest CPU scheduling algorithm is the first-come, first-served (FCFS) scheduling algorithm. With this scheme, the process that requests the CPU first is allocated the CPU first. The implementation of the FCFS policy is easily […]

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Operating System

CPU Scheduling

CPU Scheduling:- CPU scheduling is a process which allows one process to use the CPU while the execution of another process is on hold. That means in waiting for the state due to unavailability of any resource like I/O etc., thereby maximizing utilization of CPU. The job of the CPU Scheduler (the short-term scheduler) to […]

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Core JAVA

What is Input from keyboard in java ?

Input from the keyboard:- Followings are the techniques through which we can take input from keyboard. By using scanner class. By using command line argument. By using buffer-reader. By using console class. By using data input stream reader. By using command line argument Command-line Argument Command line argument is a method which user will give inputs […]

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Core JAVA

What is Block in JAVA…?

BLOCK IN JAVA:- A block in Java is a group of one or more statements enclosed in braces.A block start with ( { ) and ends with ( } ). A block statement is generally used to group together several statements, so they can be used in a situation that requires you to use a single […]

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Operating System

What is the difference between process and program?

What is the difference between process and program? The difference between process and program is Programming is a process of taking an algorithm and encoding into notation but Process is the running program of the system. a program is a group of instructions to carry out a specified task whereas the process is a program in execution. Both are the same beast […]

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Operating System

Cooperating Processes

Cooperating Processes The concurrent processes executing in the operating system may be either independent processes or cooperating processes. A process is independent if it cannot affect or be affected by the other processes executing in the system. Clearly, any process that does not share any data (temporary or persistent) with any other process is independent. […]

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Operating System

What is process Creation and process Termination ?

Process Creation Parent process creates child processes, which, in turn create other processes, forming a tree of processes. It is called process creation.  Resource sharing: ✦ Parent and child share all resources. ✦ Children share the subset of parent’s resources. ✦ Parent and child share no resources. Execution: ✦In the Operating System, the Parent process […]

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Operating System

What is Scheduler ?

Schedulers A schedule is a decision maker that selects the processes from one scheduling queue to another or allocates CPU for execution. The Operating System has three types of scheduler: Long-term scheduler or Job scheduler Short-term scheduler or CPU scheduler Medium-term scheduler   Long-term scheduler or Job scheduler The long-term scheduler or job scheduler selects […]

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Core JAVA

What is private constructor ,Factory method and Singleton class in JAVA ?

Factory Method:- If the return type of method is class name then it is known as the Factory method. Private constructor defining a “virtual” constructor. Private Constructor:- The factory constructor declared with private-keyword is known as private-constructor. If the constructor is private we cannot create an object outside class. The private constructor is used to serve […]

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Operating System

What is Process Scheduling Queues in Operating System?

Process Scheduling Queues:-  Process scheduling is an essential part of a Multiprogramming operating systems. It contains various operation such as:- Job Queue: It contains the process entered into the system for execution. This queue consists of all processes in the system; those processes are entered into the system as a new process Ready Queue:   Ready […]

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Operating System

What is Process Control Block (PCB) in Operating System ?

Process Control Block (PCB) In the operating system, Process Control Block contains the information about the process which manages the scheduling of a particular process.  Process state  Program counter  CPU registers  CPU scheduling information  Memory-management information  Accounting information  I/O status information Process state: The state may be new, ready, running, waiting, halted, and SO on. […]

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Operating System

Hardware Protection

Hardware Protection Dual-Mode Operation I/O Protection Memory Protection CPU Protection Dual-Mode Operation Sharing system resources require the operating system to ensure that an incorrect program cannot cause other programs to execute incorrectly. Provide hardware support to differentiate between at least two modes of operations. User mode – execution is done on behalf of a user. […]

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Operating System

What is process in Operating System ?

Process Concept:- The process is the running program of the system. Linux and Windows both are the multi-processes operating system. The program doesn’t allocate memory but process allocate memory. Every process allocates 4GB virtual memory. The process is two types: –1)parent process 2) the Child process. The process which is created another process is called […]

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Core JAVA

What is Abstract class and Anonymous class in java…?

Abstract and Anonymous class:- Abstract class:- If the class name is declared as an abstract keyword it is known as abstract class. An abstract class may or may not contain an abstract method. Abstract class and anonymous class almost equivalent to using a named inner class. If the class is abstract it cannot be instantiated(we […]

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Operating System

What are the services provided by the Operating-System…?

Operating System Services Following are the five services provided by operating systems to the convenience of the users. Program Execution The purpose of computer systems is to allow the user to execute programs. So the operating system provides an environment where the user can conveniently run programs. Running a program involves the allocating and deallocating […]