Preemptive and Non-Preemptive Scheduling 

Reviewing exam and find this channel. Totally game changer. Much better than professor reading slides in class

Video summary: - A CPU scheduler is a part of the operating system that determines which process to allocate the CPU to at any given time. - A dispatcher is a component of the operating system that is responsible for actually switching the CPU from one process to another according to the decision made by the CPU scheduler. - Dispatch latency refers to the time taken by the dispatcher to stop one process and start executing another process. - CPU scheduling may take place when a process: switches from running to waiting state switches from running to ready state switches from waiting to ready state terminates - Preemptive scheduling is a CPU scheduling technique where the operating system interrupts the currently executing process to allocate the CPU to a higher-priority process. - Non-preemptive scheduling is a CPU scheduling technique where the currently running process is not interrupted and continues to execute until it voluntarily releases the CPU, blocks, or completes its execution, and only then the operating system selects another process to execute.

Exam tomorrow, watching at 2x speed Edit : just realized i wrote this comment 2 years ago, life changes so quickly. Edit - after 4 years - graduated with 9.26 cgpa. Now a software engineer

Tomorrow is my exam 😂😂😂🎉🎉🎉🎉🎉 and this channel helps me a lot 😁 , love you neso ❤❤❤❤🎉🎉

Very well explained! CPU Scheduler selects the particular program that is to be assigned to the CPU for execution while Dispatcher is a program that assigns the hold of the CPU to the program selected by the scheduler and the time taken by the dispatcher to assign hold of the CPU to the program selected by scheduler is called latency. As switching is frequent task so the the latency of dispatcher should be minimal. Two ways of scheduling are non-preemptive or cooperative and preemptive. In non-preemptive a process that is in execution by the CPU is never disturbed. So it happens when the process is terminated or has switched to waiting state. Whereas in preemptive, the processor can be assigned to another process even when the already existing process was being executed. It happens when another process of very high priority needs to executed first.

This video is really helpful! I'm not a native English speaker but I fully understand all the concepts, thank you sir!

This did a lovely job of explaining the concepts, thanks x

So well explained, each and every point is explained perfectly

very clear and thorough explanation ! Thank you sir !

Please add more videos frequently into Operating system playlist,I have watched all 38 videos now ,they were great , waiting for the next video.Thanks

Very good teacher. I'm enjoying the lectures.

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Succinct and clear explanation. Thank you very much, sir. Keep up the great work.

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Thank you very much. It is very understandable once again.

I like your way of teaching. Also your English is very good too.

Thank you so much for this video

beautifully explained!

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Very helpful, thank you

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1) Scheduler: Selects a process in the ready queue to be given the CPU 2) Dispatcher: Gives the control of the CPU to the process selected by the scheduler. The time between the stopping and starting a process execution is called dispatch latency. 3) Preemptive: When a process change from running state to ready state (interrupt) or from waiting to ready state (I/O) 4) Nonpreemptive or cooperative scheduling: When a process change from running to waiting state (I/O) or terminates. A new process in the ready queue (if it is not empty) have to selected to be given the CPU.

these lectures hit different an hour before exam

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good explanation

exam after 3 hours watching in 2x but i want 4x speed...😥😆

great video, thank you

well explained!!

Thanks for taking galvin to videos 😁

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Thank you sir👍🏾

This explains so much about why computers do weird shit

Please create a playlist for Data structure and Algorithms ,it is the need of the hour......

Thanks

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For simplicity sake, We need to understand at what process's state does it finishes it's execution whether it is in waiting state and termination state. On another hand, when it is in ready state means the process is not done yet or it is halfway of it's execution or maybe halfway of it's termination state?. So, if the process is in "ready state" We can schedule the processes that need to use cpu based on their priority?. As for the non-pre emptive scheduling, Either we want to give the cpu to another processes or not, We have no choice because the process has finished it's execution Meaning no need to use CPU again. So just give it to another processes. As for the name "pre-emptive", I am suggesting it needs to empty the cpu first before giving it to other processes. Hopefully this is correct.

thanks for the video sir, where can we get the slides that you are using?

Sir please upload the videos about process sychorinzation 🙏

Thanks Sir...

Amazing Explainetion : one night before exam 😜

Thankyou sir

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Thankuu

GC state runs in preemptive which means the CLR needs to turn those cooperative threads into preemptive threads for GC to run. said that, if the GC thread pertains to the same process , if the process is taken away from cpu ,how the GC tread will run if it needs to run in preemptive state ???? do you mean process thread when you said process? right? meaning that a process thread is suspended (interrupted/waited) while another GC thread on the main process is run.

Preemptive and Non-Preemptive Scheduling actually explained at: 13:36

he said that among the process in the ready queue, CPU scheduler is the one which selects the process who will get CPU. That means CPU scheduler is also one of the processes in the ready queue. Right?

Awesome

My Savior

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why is waiting state to ready state preemptive ? It went to Waiting state for I/O only after running state , right?

who will decide priority for the scheduling sir

❤️ thats the comment

I'm garbage. This is the exact same concept that is on book the book "Operating System Concepts" page 202 and I had no clue what i was reading until i watched this video.

isn't CPU scheduler the Kernel of operating system??

Sir please upload course of Data analysis with python

All the lectures are made from Galvin's book. Even some lines are exactly the same

I was here on 17 April 2023

Add .net programming videos please

exam today at 7 pm and here i am watching this vid at 6:17 pm with x2 speed

When she text you for netflix and chill but you decline replying you're binging OS mechanisms and design for your imaginary ASM/C OS on YT.

08:30 why is ready state to running state not considered?

can a operating system scheduling be both preemptive and non preemptive?

can i have pdf notes???

process switches from running state to ready state due to some interruptions. Can someone give me practical example of such interrupts?

I have a project tomorrow watching at 4x

yeah I still don't get it

please provide these slides in a g drive sir. it would help in revision.

sir ji notes mil jayenge kya website pr

Either exam or not 2x is best

This is how commerce guys can pass os exam.

Sir please make videos under 10 to 15 minutes not longer

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3

washout 2D

I think, the correct pronounciation is "cedular"... Not "skejular".

Thank you sir

Thanks sir