<a href=”http://www.freepik.com">Designed by pch.vector / Freepik</a>

When your journey to implement your own Operating System this is the part you are going to learn some serial ports. use mouse, mouse movements.

you need to create C functions and some header files and call them via assembly.

Then you have to learn Priority Based scheduling.

Priority Based Scheduling

Each process is assigned a priority

Priority are two types

Static priority — typically set at start of execution

Dynamic priority — Scheduler can change the process priority during execution in order to archive scheduling goals.

To process those priority levels we use multilevel ques.

CPU Scheduler

Types of process- I/O bound, CPU bound

Several CPU scheduling Algorithms and scheduling criteria

various Scheduling algorithms ex- FCFS Algorithm

then Convoy Effect- All process wait for some big process to get off the CPU.

ex2- Shortest Job First (SJF Algorithm) — No preemption algorithm. this algorithm scheduled process to ascending order using CPU Burst time.

ex3- SRTF Algorithm

ex4- Round Robin scheduling — Run process for a time slice then move to back to ready queue.

Process Types

Realtime — have deadlines, Should never blocked by low priority task

Normal Processes-Interactive, Batch

Completely Fair Scheduling(CFS)

This is the newest scheduler currently used in Linux systems

The Linux scheduler since 2007

By Lngo Molnar

No heuristics

Elegant handling of I/O and CPU bound process.



Get the Medium app

A button that says 'Download on the App Store', and if clicked it will lead you to the iOS App store
A button that says 'Get it on, Google Play', and if clicked it will lead you to the Google Play store