Round Robin Advantage Vs Disadvantage

Duration: 9 min

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Quantitative Aptitude: Ratio and Proportion (Ratios), Data Interpretation, Mixture and Alligation, Permutation and Combination, Number System, Sequence and Series (Series), Speed Time and Distance, Speed Mathematics and Basic Mathematics, Algebra, Percentage, Profit and Loss, Simple Interest and Compound Interest, Powers and Exponents (Surds and Indices), Time and Work, Mensuration and Geometry, Partnership
Reasoning Ability: Series (Number and Letter Series) (Numerical Relations and Reasoning), Coding Decoding, Data Sufficiency, Seating Arrangements, Deductive and Inductive Reasoning (Logical Deduction and Induction) (Prepositional Reasoning), Directions (Direction Test), Ranking, Order and Sequence, Syllogisms, Blood Relations, Puzzle Solving (Puzzles), Inequality, Machine Input-Output
English Language: Vocabulary, Noun, Subject Verb Agreement (Verb Noun Agreement), Adjectives, Tenses, Comprehension / Reading Comprehension / Unseen Passages (Critical Reasoning) (Paragraph Questions), Cloze Test (Cloze Passage), Sentence Correction (Error Correction), Sentence Completion (Fill in the blanks), Sentence Re-arrangements (Para Jumbles) (Narrative Sequencing), Sentence Construction, Pronoun, Preposition, Conjunction, Adverb, Verb, Modals, Articles, Determiner, Interjection
General Awareness: Evolution of Indian Banking (Banking & Financial Awareness), GK- Current Affairs, Static General Knowledge, Indian Economy
C Concepts + MCQs (IT Specialist): C Programming by Yash Sir, C Language Core
Java (IT Specialist): Java
Python (IT Specialist): Python for Placements by Yash Sir, Python Basics
OOPs (IT Specialist): Object Oriented Programming (OOPS)
DBMS (IT Specialist): Basics of DBMS, ER Diagram, Relational Model & Functional Dependencies, Keys & Integrity Constraints, Normalization (1NF - BCNF), Decomposition Properties & 4NF, File Organization & Indexing, Relational Algebra, Relational Calculus, Transaction Management, Concurrency Control, Database Recovery, ORDBMS, Database Security & Authorization, Query Processing & Optimization, Enhanced Data Models, Data Warehousing & Mining, Big Data Systems, NoSQL
SQL (IT Specialist): SQL
Software Engineering (IT Specialist): Fundamentals of Software Engineering, Software Requirements and Quality Assurance, Software Design, Estimation and Metrics, Software Testing, Software Maintenance and Configuration Management
Data Structure (IT Specialist): Introduction to DS, Array, Stack, Queue, Linked List, Tree, Graphs, Hashing
Operating System (IT Specialist): Introduction to OS, Process Management, CPU Scheduling, Process Synchronization, Deadlock, Threads & Process Creation, Memory Management, Virtual Memory, Disc Scheduling, File Management, Windows OS, Linux OS, Security, Distributed Systems, Virtual Machines
Compiler Design (IT Specialist): Intro to Compilers, Lexical Analysis, Grammar & CFG, Syntax Analysis: Top-Down, Syntax Analysis: Bottom-Up, Semantic Analysis & SDT, Intermediate Code Gen, Code Optimization, Run Time Environment
Computer Architecture (IT Specialist): Basics of COA, Floating Point Rep, Cache Memory Organization, Input Output Organisation, Pipelining, Instr Formats & Modes, Control Unit Design, Register Transfer and Microoperations, Multiprocessors, Programming the Basic Computer
Data Communication & Networking (IT Specialist): Introduction to CN, Data Communication, DLL: Access Control, DLL: Flow Control, DLL: Error Control, DLL: Framing, Data Link Layer - Ethernet, Net Layer: IPv4 & Proto, Net Layer: IP Addressing, Net Layer:Routing Protocol, Transport Layer Services, TL: Congestion & UDP, Application Layer, Hardware basics, Network Security
Descriptive Test (Main Exam): English Writing Ability

AI summary & chapters

AI Summary

An AI-generated summary of this video lecture.

This educational video provides a comprehensive lecture on the Round Robin (RR) CPU scheduling algorithm. The instructor begins by explaining the core principles of RR, including the concept of a time quantum (q) and how it ensures fairness by giving each of the n processes in the ready queue a turn to execute for at most q time units. A key point is that the maximum waiting time for a process before its next quantum is (n-1)q. The lecture then transitions to the impact of the time quantum's size, explaining that a very large quantum makes RR behave like First-Come, First-Served (FCFS), while a very small quantum creates the illusion of multiple processors, a concept known as processor sharing. The video concludes with a detailed analysis of RR's advantages and disadvantages. Advantages include excellent average response time, making it ideal for time-sharing and interactive systems, and its nature as a preemptive SJF implementation. Disadvantages include the potential for longer processes to starve and the fact that performance is highly sensitive to the time quantum's value, as it affects both average response time and CPU utilization. A table of process metrics is used to illustrate the calculation of completion time, turn around time, and waiting time.

Chapters

0:00 – 2:00 00:00-02:00
The video opens with a slide defining the Round Robin (RR) scheduling algorithm. The instructor explains that if there are n processes in the ready queue and the time quantum is q, each process gets 1/n of the CPU time in chunks of at most q time units. He emphasizes that each process must wait no longer than (n-1)q time units for its next quantum. To illustrate this, he draws a timeline on the whiteboard, labeling processes P1, P2, and P3, and shows how they would be scheduled in a round-robin fashion, with each getting a slice of time q. He also writes the formula for the maximum waiting time as (n-1)q.
2:00 – 5:00 02:00-05:00
The instructor discusses the effect of the time quantum's size. He states that if the time quantum is extremely large, RR behaves like the FCFS policy. Conversely, if the time quantum is extremely small (e.g., 1 millisecond), the RR approach is called processor sharing, where it creates the illusion that each of the n processes has its own processor running at 1/n the speed of the real processor. He draws a diagram to show the transition from a large quantum (max) leading to FCFS to a small quantum (min) leading to processor sharing. He also mentions that the effect of context switching on performance must be considered.
5:00 – 8:37 05:00-08:37
The video presents a slide on the advantages and disadvantages of RR. Advantages include performing best in terms of average response time, making it suitable for time-sharing, client-server, and interactive systems, and being a kind of SJF implementation. The instructor then moves to the disadvantages: longer processes may starve, and performance is heavily dependent on the time quantum. He explains that a very small quantum gives a good average response time but causes many context switches, while a very large quantum results in poor average response time but fewer context switches and better CPU utilization. The video concludes with a table showing process metrics (P0 to P5) and a Gantt chart, which the instructor uses to calculate completion time, turn around time (TAT = CT - AT), and waiting time (WT = TAT - BT).

The lecture systematically builds an understanding of the Round Robin scheduling algorithm. It starts with the fundamental definition and fairness guarantee, using a timeline diagram to visualize the process. It then explores the critical parameter of the time quantum, showing how its size dictates the algorithm's behavior, from FCFS to processor sharing. Finally, it provides a balanced view by outlining the key advantages, such as excellent response time for interactive systems, and the main disadvantages, including starvation and the trade-off between response time and CPU utilization. The use of a process table and Gantt chart provides a practical example of how to calculate key performance metrics, reinforcing the theoretical concepts.