Discussion Assignment Unit 4 PDF

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In unit 4, we are introduced to the concepts of abstraction and scheduling
For your Discussion Forum Post:
Using one of the referenced website articles or an article of your choice,
To discuss single-queue versus multi-queue scheduling.

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Discussion Assignment Unit 4

In unit 4, we are introduced to the concepts of abstraction and scheduling For your Discussion Forum Post: Using one of the referenced website articles or an article of your choice, To discuss single-queue versus multi-queue scheduling. After you respond to the assignment, you are then required to both give a rating and also leave a 250-word significant comment, to at least three (3) of your peers' responses, in order to receive full credit. Rate only the substantial responses that contribute to the promotion of the discussion, and not the comments of your peers. Please use your coursebook as your main source - it helps when you begin taking the upcoming graded quizzes and final exam. *PLEASE, read the documents I posted in the Course Forum. **Make sure you understand "MLFQ", some of you may see it AGAIN. *** What is log2 ?, you will need to know this later in the course **** learn how to convert Hexadecimal to Binary

Additional References Arpaci-Dusseau, R. H., & Arpaci-Dusseau, A. C. (2018). Operating Systems: Three Easy Pieces, Chapters 10.4-10.5. Madison, WI: Arpaci-Dusseau Books. Retrieved from http://pages.cs.wisc.edu/~remzi/OSTEP/ Ellingwood, J. (2014). CIDR Notation. Understanding IP Addresses, Subnets, and CIDR Notation for Networking. DigitalOcean. Retrieved from https://www.digitalocean.com/community/tutorials/understanding-ip-addresses-subnets-and-cidrnotation-for-networking GeeksforGeeks. (n.d.). Multilevel feedback queue scheduling (MLFQ) CPU scheduling. A computer science portal for geeks. Retrieved from https://www.geeksforgeeks.org/multilevel-feedback-queue-scheduling-mlfq-cpu-scheduling/ (n. d.). Parallel Programming Concepts and High-Performance Computing: Synchronization Overhead. Cornell Virtual Workshop. Retrieved from https://cvw.cac.cornell.edu/Parallel/synch

Answer: Discuss single-queue versus multi-queue scheduling. Single-queue scheduling orderly approach is working by First Come First Served principle by which in its turn queries arrive to Operating System. I think First Come First Served is also a synonym of First in First out. In terms of short-term scheduling, the Central processing Unit scheduler also called a dispatcher which makes a decision on what processes from the list are ready for execution. When a system call was generated by a process with reading or write instruction the process should be blocked in order to clear the path for another process ready for the execution to be executed while the scheduler gets yet another process from the queue. Each process gets blocked when its CPU time elapses. The single queue scheduling mechanism is straightforward and relatively easy to implement. Processes are being executed one by one by the first in first out mechanism. With such a mechanism the situation where a process is put on hold for an unreasonably long time because of its low priority is impossible. On the other hand, such an approach has its drawbacks. Such an approach is not optimized and for example, short processes which might be executed in seconds should wait in the queue before a longer process is done. Thus, the overall system with such a mechanism is relatively slow. The multi-queue scheduling mechanism has a different approach to handling processes. It divides the main queue into so to speak sub-queues that have their own individual scheduling priorities. Thus, they have different time-responses rates. Factors for such divisions are process type, priority type, memory size, etc. Even Fist in first out mechanism can be applied in some of those sub-queues as a result of such differences among them. A multi-queue scheduling mechanism won’t allow for process stagnation but on the other hand, frequent context switching reduces overall performance. Thus, we can conclude that there is no one better solution. Performance depends on the situation. For a similar queue of processes, the single-queue mechanism would be better in my opinion. For a queue of processes that can be divided by classes, a multi-queue approach would be more preferable.

References: Arpaci-Dusseau, R. & Arpaci-Dusseau, A. (2012). Operating systems: Three easy pieces. Madison, WI: University of Wisconsin-Madison. Retrieved from http://pages.cs.wisc.edu Operating System - Process Scheduling. (n.d.). Retrieved from: https://www.tutorialspoint.com...