Round Robin PQ

Duration: 13 min

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Inside: a video lesson and guided study material.

Module outline

  1. General Intelligence & Reasoning: Analogy, Non Verbal Reasoning (Spatial Aptitude) (Spatial Reasoning) (Visual Reasoning), Series (Number and Letter Series) (Numerical Relations and Reasoning), Coding Decoding, Blood Relations, Directions (Direction Test), Ranking, Order and Sequence, Logical Sequence Of Words, Syllogisms, Venn Diagram, Deductive and Inductive Reasoning (Logical Deduction and Induction) (Prepositional Reasoning), Selection Decision Table (Decision Making), Data Sufficiency, Puzzle Solving (Puzzles), Data Arrangement, Cubes & Dices, Calendar, Clock, Arithmetic, Number System, HCF LCM, Verbal Analogy (Word Based Analogy), Visual Recognition and Figure Completion, Paper Folding and Cutting, Transformation of Shapes, Clocks and Calendars, Direction Sense, Cubes and Dice, Patterns in Two-Dimensional Figures, Seating Arrangements, Analogy and Classification, Logical Deduction and Induction, Alphabet and Word Tests, Mathematical Operations, Series Completion, Simplification and Approximation, Coding and Decoding, Numerical Reasoning, Assembling and Grouping of Shapes, Three-Dimensional Patterns and Visualization, Vocabulary, Number System, Averages, Mixtures and Alligation, Simple and Compound Interest, Percentages, Algebra, Speed, Time and Distance, Seating and Arrangement Puzzles, Traverse Surveying, Order, Ranking and Sequence, Constraint Puzzles, Syllogisms and Venn Diagrams, Reading Comprehension, Critical Reasoning, Permutations and Combinations, Narrative Sequencing, Project Monitoring, Resources and Safety, Profit, Loss and Discount, Ratio and Proportion, Time and Work, Mensuration, Data Interpretation, Powers, Surds and Logarithms, Sequences and Series, Articles and Determiners, Sentence Completion, Data Sufficiency, Blood Relations, Simple Interest and Compound Interest, Mixture and Alligation, Sequence and Series (Series), Speed Time and Distance, Algebra, Profit and Loss, Powers and Exponents (Surds and Indices), Permutation and Combination
  2. General Awareness: Physics, Chemistry, Biology, History, Geography, Polity, Indian Economy, Environment, Static General Knowledge, GK- Current Affairs, Artificial Intelligence, MS Office Applications, Terms & Abbreviations, Keyboard Shortcuts, Evolution of Indian Banking (Banking & Financial Awareness), Emerging Tech Trends
  3. Engineering Mathematics: Set Theory, Relations, Functions, Graph Theory, Group Theory, Propositional and Predicate Logic, Linear Algebra, Calculus, Probability, Statistics, Signal Space and Optimum Detection, Probability, Statistics
  4. Digital Logic: Digital Systems & Boolean Basics, Logic Gates & Hardware, Boolean Expression, Boolean Minimization, Combinational Circuit, Sequential Circuits, Number System, Number Representation, Floating Point Rep, Number Systems and Codes, Registers and Counters, Boolean Algebra and Logic Gates, Microprocessors and Microcontrollers, Logic Families and CMOS Logic, Microprocessors, Logic Gates and Boolean Algebra, Minimization of Boolean Functions, Timing, Hazards and Testing, Logic Families, Combinational Logic Design, Arithmetic Circuits, Waveform Generators and Timer Circuits, Semiconductor Memories and Programmable Logic Devices, Combinational Logic Circuits, Latches and Flip-Flops, Finite State Machines, Sequential Circuits and State Machines, Minimization of Boolean Functions, Arithmetic Circuits, Latches and Flip-Flops, Number Systems and Codes, Registers and Counters
  5. Computer Organisation & Architecture: Basics of COA, Cache Memory Organization, Input Output Organisation, Pipelining, Instr Formats & Modes, Control Unit Design, Programming the Basic Computer, Register Transfer and Microoperations, Semiconductor Memories and Programmable Logic, Processor Organization and Instructions, Memory Hierarchy and Input/Output, Registers and Counters
  6. Programming & Data Structures: C Fundamentals, Control Flow, Functions, Arrays & Pointers, Storage Classes, Structures & Enums, DMA, Macros, Scoping & File Handling, Introduction to DS, Array, Stack, Queue, Linked List, Tree, Graphs, Hashing, HTML Basics, OOPS with C++, Java, Object Oriented Technology
  7. Databases: Basics of DBMS, ER Diagram, Relational Model & Functional Dependencies, Keys & Integrity Constraints, Normalization (1NF - BCNF), Decomposition Properties & 4NF, File Organization & Indexing, Relational Algebra, SQL, Relational Calculus, Transaction Management, Concurrency Control, Database Recovery, Database Security & Authorization
  8. Algorithms: Algorithm Analysis, Time Complexity Analysis, Sorting Algorithms, Greedy Algorithms, Dynamic Programming, Minimum Spanning Trees, Shortest Path Algos
  9. Theory of Computation: Introduction to TOC, Deterministic FA (DFA), Non-Deterministic FA, Regular Expressions, Grammar, Regular Language Properties, Moore & Mealy Machines, Pushdown Automata & CFG, Turing Machines, Complexity Theory
  10. Compiler Design: 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
  11. Operating System: Introduction to OS, Process Management, CPU Scheduling, Process Synchronization, Threads & Process Creation, Deadlock, Memory Management, Virtual Memory, Disc Scheduling, File Management, Security, Windows OS, Distributed Systems, Unix OS, Linux OS
  12. Computer Networks: Introduction to CN, 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, Data Communication, Website, Browser & Services, Web Design & Development, Network Security, Cyber Threats and Malware Attacks, Cyber Safety and Security
  13. Full Length Mock Tests:
  14. Sectional Tests:
  15. Paper 2 - Full-length Mock Tests:
AI summary & chapters

AI Summary

An AI-generated summary of this video lecture.

The video demonstrates a Round Robin scheduling practice problem. The instructor sets up a table for six processes (P0-P5) with arrival and burst times, then constructs a Gantt chart using a time quantum of 3 units. A queue box tracks the ready processes as they are scheduled. The instructor calculates completion times, turnaround times, and waiting times for each process, ultimately deriving the average turnaround time and average waiting time. The solution involves tracking process execution across multiple time slices and managing the ready queue as new processes arrive and others complete.

Chapters

  1. 0:00 – 2:00 00:00-02:00

    The instructor introduces the problem: calculating average TAT and WT using Round Robin with a time quantum of 3 units. A table is set up with columns for P. No, Arrival Time (AT), Burst Time (BT), Completion Time (CT), TAT = CT - AT, and WT = TAT - BT. The arrival times are filled in as 5, 4, 3, 1, 2, 6 for P0 through P5, and burst times are listed as 5, 6, 7, 9, 2, 3. The instructor begins sketching a Gantt chart, starting with an idle region from 0 to 1, then scheduling P3 first since it has the earliest arrival time.

  2. 2:00 – 5:00 02:00-05:00

    The Gantt chart expands to show P3 executing from 1 to 4, followed by P4 from 4 to 6, P0 from 6 to 9, and P1 from 9 to 12. A pink Queue box on the right tracks the ready processes, initially showing P4, P0, P3, P5, then adding P2 and another P4 as processes arrive and wait. The instructor explains how processes are added to the queue upon arrival and how the quantum of 3 units determines when a process is preempted and sent to the back of the queue.

  3. 5:00 – 10:00 05:00-10:00

    The Gantt chart continues with P3 resuming from 12 to 15, then P0 from 15 to 18, P5 from 18 to 21, and P0 again from 21 to 24. The queue box updates to reflect the changing ready state, showing sequences like P1, P5, P3, P2, P4 shifting to longer sequences including P0 and P1. The instructor fills in the Burst Time column with values 8, 3, 4, 3, 2, 3 in pink and green ink, while the AT column remains 5, 4, 3, 1, 2, 6. The process of tracking remaining burst times and re-queuing preempted processes is emphasized.

  4. 10:00 – 13:20 10:00-13:20

    The instructor completes the table by filling in the CT column with values 32, 27, 30, 30, 06, 01, then calculates TAT as 27, 23, 27, 29, 04, 15, and WT as 22, 17, 23, 20, 02, 12. The final Gantt chart shows the complete execution sequence with time markers up to 33. The instructor computes the averages, showing 76/6 = 12.8 for average TAT and 96/6 for average WT. The queue box displays the final sequence P1 P0 P1 P3 P0 P5 P0 P1 P3 P0 P5, illustrating the full scheduling order.

This lecture provides a step-by-step worked example of Round Robin scheduling. The key concepts include: (1) setting up a process table with arrival and burst times, (2) constructing a Gantt chart that respects the time quantum, (3) maintaining a ready queue that updates as processes arrive and are preempted, and (4) calculating completion, turnaround, and waiting times. The method emphasizes that when a process's quantum expires, it is sent to the back of the queue with its remaining burst time. New arrivals are added to the queue in order of arrival. The final metrics are derived by summing individual TAT and WT values and dividing by the number of processes. The example demonstrates how to handle multiple preemptions and arrivals within a single scheduling problem.

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