CPU Burst
the amount of time the process uses the processor before it is no longer ready
Process Scheduling in OS
The activity of the process manager that handles the removal of the running process from the CPU and the selection of another process on the basis of a particular strategy. Process scheduling is an essential part of a Multiprogramming operating systems.
Preemptive Scheduling
Preemptive scheduling is used when a process switches from running state to ready state or from waiting state to ready state. The resources (mainly CPU cycles) are allocated to the process for the limited amount of time and then is taken away, and the process is again placed back in the ready queue if that process still has CPU burst time remaining. That process stays in ready queue till it gets next chance to execute.
Non-Preemptive Scheduling
Non-preemptive Scheduling is used when a process terminates, or a process switches from running to waiting state. In this scheduling, once the resources (CPU cycles) is allocated to a process, the process holds the CPU till it gets terminated or it reaches a waiting state. In case of non-preemptive scheduling does not interrupt a process running CPU in middle of the execution. Instead, it waits till the process complete its CPU burst time and then it can allocate the CPU to another process.
Asymmetric Multiprocessing
Asymmetric multiprocessor systems are a part of multiprocessor systems along with symmetric multiprocessor systems. Multiprocessor systems have multiple processors working in parallel that share the computer clock, memory, bus, peripheral devices etc.
Symmetric Multiprocessing
In symmetric multiprocessing, multiple processors share a common memory and operating system. All of these processors work in tandem to execute processes. The operating system treats all the processors equally, and no processor is reserved for special purposes.
Dispatcher in OS
A dispatcher is a module, it connects the CPU to the process selected by the short-term scheduler.
Round Robin scheduling
Round Robin is a CPU scheduling algorithm where each process is assigned a fixed time slot in a cyclic way.
First Come First Serve (FCFS)
First Come First Serve (FCFS) is an operating system scheduling algorithm that automatically executes queued requests and processes in order of their arrival.
Shortest Job First(SJF)
Shortest Job First scheduling works on the process with the shortest burst time or duration first.