An interactive process communicates with the user by receiving commands or data from the keyboard or a pointing device and responding by generating output to an output device. (monitor, printer, etc) A time quantum, Q, is a small amount of time (typically 10 to 100 milliseconds) during which a process is allowed to use the CPU. The round-robin (RR)…
A batch process performs a long-running and generally repetitive task that does not require any intervention from the user. Ex: Payroll, insurance claims processing, weather prediction, scientific calculations. These are typically run on a server and not a desktop user machine. The FIFO (First-In-First-Out) algorithm, also known as FCFS (First-Come-First-Serve), schedules processes strictly according to the process arrival…
Long-term scheduling decides when a process should enter the ready state and start competing for the CPU. It also manages those which are suspended, to acknowledge when they are ready to move to the ready list. Short-term scheduling decides which of the ready processes should run next on the CPU. Most processes move because of the short…
An application implemented as a single process follows a single path of execution through the program. Most (All) applications you’ve written at this point are single process applications. When a process is blocked by a resource, then the whole process is blocked. However, many applications have other parts of the application that could continue to…
The OS has to track resources so that it knows when those resources are available for use. If it “just let” processes use resources, they could step on the resources and crash the system as a resource can only be used by a single process at a time. So the OS uses an Resource Control…
A process creation hierarchy is a graphical representation of the dynamically changing parent-child relationships among all processes. The process creation hierarchy changes each time a process is created or destroyed. When a process initiates the creation of a child process, the OS executes a create process function. The create process function allocates a new PCB, fills the PCB entries…
CPU_state – When the process is stopped, the current state of the CPU, consisting of various hardware registers and flags, is saved in this field to be reloaded when the process resumes. PCB Data Description Data Stored As Can Change process_state This is the state of the process, running, ready, or blocked most often. Integer…
A process is an instance of a program being executed by an OS. The OS manages the processes in something called a Process Control Block (PCB). This helps it keep track of what is running, how much memory is being used and where, the program being run, the current instruction address, etc. Your operating system as a…
