Practice Question

Duration: 17 min

This video lesson is available to enrolled students.

Return to /learn/BIHAR-STET-COMPUTER-SCIENCE-COMPLETE-COURSE/unit-5-operating-system/cpu-scheduling/priority-scheduling/asset-practice-question-3685 after enrolling

Inside: a video lesson and guided study material.

Module outline

  1. About the course: About the Course
  2. Mathematical Aptitude: Number System, HCF LCM, Divisibility Rules, Percentage, Ratio and Proportion (Ratios), Average, Profit and Loss, Time and Work, Mensuration and Geometry, Simple Interest and Compound Interest, Speed Time and Distance, Age Problems, Mixture and Alligation, Algebra, Powers and Exponents (Surds and Indices), Pipe and Cistern, Trigonometry, Statistics, Data Interpretation, Arithmetic
  3. Logical Reasoning: Series (Number and Letter Series) (Numerical Relations and Reasoning), Coding Decoding, Analogy, Blood Relations, Directions (Direction Test), Ranking, Order and Sequence, Non Verbal Reasoning (Spatial Aptitude) (Spatial Reasoning) (Visual Reasoning), Seating Arrangements, Syllogisms, Venn Diagram, Puzzle Solving (Puzzles), Logical Sequence Of Words, Deductive and Inductive Reasoning (Logical Deduction and Induction) (Prepositional Reasoning), Analytical Reasoning (Counting Figures Reasoning), Cubes & Dices, Calendar, Clock
  4. General Knowledge: Physics, Chemistry, Biology, History, Geography, Polity, Indian Economy, GK- Current Affairs, Static General Knowledge
  5. Art of Teaching: Nature, Objectives & Characteristics of Teaching, Learners & Learning Process, Factors Affecting Teaching, Methods of Teaching, Classroom Management & Communication, Teaching-Learning Aids & ICT Integration, Evaluation, Assessment & Measurement, Professional Development & Ethics, Policies, Acts & Contemporary Issues, Curriculum & School Environment, Guidance, Counselling & Mental Health, Inclusive Education & Special Needs, Micro-Teaching & Teaching Skills, Lesson Planning
  6. Environmental Science: Environment
  7. Unit 1 | Digital Electronics: Digital Systems & Boolean Basics, Logic Gates & Hardware, Boolean Expression, Boolean Minimization, Combinational Circuit, Sequential Circuits, Number System, Number Representation
  8. Unit 2 | COA: Basics of COA, Floating Point Rep, Cache Memory Organization, Input Output Organisation, Instr Formats & Modes, Control Unit Design, Register Transfer and Microoperations, Programming the Basic Computer
  9. Unit 3 | C Programming: C Fundamentals, Control Flow, Functions, Arrays & Pointers, Storage Classes, Structures & Enums, DMA, Macros, Scoping & File Handling
  10. Unit 3 | Data Structures: Introduction to DS, Array, Stack, Queue, Linked List, Tree, Graphs, Hashing
  11. Unit 4 | Algorithms: Algorithm Analysis, Time Complexity Analysis, Sorting Algorithms, Dynamic Programming, Minimum Spanning Trees, Shortest Path Algos, Advanced Algorithms
  12. Unit 5 | Operating System: Introduction to OS, Process Management, CPU Scheduling, Process Synchronization, Threads & Process Creation, Deadlock, Memory Management, Virtual Memory, Disc Scheduling, File Management
  13. Unit 6 | Database Management System: Basics of DBMS, ER Diagram, Relational Model & Functional Dependencies, Keys & Integrity Constraints, Normalization (1NF - BCNF), Decomposition Properties & 4NF, File Organization & Indexing, Relational Algebra, SQL, Transaction Management, Concurrency Control
  14. Unit 7 | Computer Networks: 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
  15. Unit 8 | Software Engineering: Fundamentals of Software Engineering, Software Requirements and Quality Assurance, Software Design, Estimation and Metrics, Software Testing, Software Maintenance and Configuration Management
  16. Unit 9 | Object Oriented Programming: OOPS with C++
  17. Unit 10 | Web Development: HTML Basics, CSS, JavaScript-Basics, XML
  18. Unit 11 | 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
  19. Unit 12 | IoT: Emerging Tech Trends, Cloud Computing
  20. Unit 13 | Artificial Intelligence: Approaches to AI, Search Algorithms, Game Playing, Knowledge Representation, Natural Language Processing, Artificial Neural Networks, Genetic Algorithms
  21. Unit 14 | E-Commerce: Electronic Data Interchange and E-Commerce, Role of Internet and Web Services, Security in Mobile and Wireless Computing, Physical Security and Cryptography Basics, Cyber Safety and Security
  22. Unit 15 | Multimedia: Multimedia
  23. Unit 16 | Python: Introduction to Python, Tokens, Variables, Data Types, I/O, Operators & Expressions, Control Flow & Looping, Collections & Strings, Functions & Modules, File Handling & Data Analysis, DSA using Python
  24. Full Length Mock Tests — General Paper:
  25. Full Length Mock Tests — Computer Science (Paper II):
AI summary & chapters

AI Summary

An AI-generated summary of this video lecture.

This lecture is a practice question on CPU scheduling, specifically calculating the Average Turnaround Time (TAT) and Average Waiting Time (WT) using both Preemptive and Non-Preemptive Priority Scheduling. The instructor presents a table with four processes (P0 to P3) and their Arrival Times (AT), Burst Times (BT), and Priorities. The rule is that a lower priority number indicates a higher priority. The instructor first determines the execution order based on priority (P1, P3, P2, P0) and then constructs a Gantt chart for the Non-Preemptive case, showing process blocks P0, P1, P3, P2 with time marks 50, 70, 110, 210. He then transitions to the Preemptive case, where he updates the remaining burst times (e.g., 50→30, 20→0, 100→80) and constructs a new Gantt chart with boundary times 0, 30, 40, 60. Throughout the video, the instructor uses a whiteboard to draw the Gantt charts and a state diagram with 'Ready', 'Running', and 'Terminated' states to track the processes. The final timeline shows a Gantt chart with time marks 0, 20, 40, 60, 100, 180, 210, indicating the completion of the Preemptive scheduling calculation.

Chapters

  1. 0:00 – 2:00 00:00-02:00

    The instructor introduces the practice question: 'Calculate the Average Turnaround Time (TAT) and Average Waiting Time (WT) using both Preemptive and Non-Preemptive Priority Scheduling.' A table is displayed with columns for P. No, AT, BT, Priority, CT, TAT = CT - AT, and WT = TAT - BT. The AT column lists 50, 20, 100, 40 (later corrected to 0, 20, 40, 60) and the Priority column lists 4, 1(h), 3, 2. The instructor points to the priority column and writes the sequence P1, P3, P2, P0, indicating the order of execution based on priority, with a note that a lower priority number indicates a higher priority.

  2. 2:00 – 5:00 02:00-05:00

    The instructor begins the Non-Preemptive Priority Scheduling calculation. The table lists P0 (0, 50, 4), P1 (20, 20, 1(h)), P2 (40, 100, 3), P3 (60, 40, 2). He draws a green Gantt-style bar at the bottom, filling in P0 then P1 with time marks 50 and 70. He also sketches a diagram at the right showing 'Ready', 'Running', and 'Terminated' circles to track the state of the processes. The instructor points to the 'Non-Preemptive' label circled in pink, emphasizing the current method.

  3. 5:00 – 10:00 05:00-10:00

    The Non-Preemptive Gantt chart is completed, showing process blocks P0, P1, P3, P2 with time marks 50, 70, 110, 210. The instructor uses a pink pen to gesture toward the green rectangle outline below the table. He then sketches three green ovals on the right labeled 'Ready', 'Running', and 'Ternate' (Terminated), with arrows connecting them. In the 'Running' oval, 'P1' appears, while the 'Ready' oval shows 'P0' and 'P1' crossed out in pink, indicating the transition of processes between states.

  4. 10:00 – 15:00 10:00-15:00

    The instructor transitions to the Preemptive Priority Scheduling calculation. The whiteboard table shows several BT entries crossed out and rewritten (50→30, 20→0, 100→80), representing the remaining burst times. A Gantt chart at the bottom extends from 'P0 | P1' to 'P0 | P1 | P2 | P3', with boundary times 0, 30, 40, 60 marked beneath it. Green hand-drawn ovals on the right are labeled 'Ready', 'Running', and 'Rem Data', each containing process names such as P0, P1, P2, to track the preemptive state changes.

  5. 15:00 – 16:33 15:00-16:33

    The Preemptive Gantt chart is progressively filled with process labels P0, P1, P2, P3 and time marks 0, 20, 40, 60, 100, 180, 210. Green handwritten notes on the right group processes under 'Ready', 'Running', and 'Time/Date' with several entries crossed out in red. The instructor stands before the digital whiteboard, completing the visualization of the Preemptive scheduling timeline, which allows for the final calculation of TAT and WT for both methods.

The lecture focuses on solving a CPU scheduling problem involving Preemptive and Non-Preemptive Priority Scheduling. The key concepts include the definition of Turnaround Time (TAT = CT - AT) and Waiting Time (WT = TAT - BT), and the rule that a lower priority number signifies higher priority. The instructor demonstrates the step-by-step process of determining the execution order based on priority and arrival time. For the Non-Preemptive case, the Gantt chart is built by running each process to completion once it starts, resulting in a timeline of P0, P1, P3, P2. For the Preemptive case, the instructor updates the remaining burst times and adjusts the Gantt chart to reflect preemptions, resulting in a more complex timeline with multiple state transitions. The use of state diagrams ('Ready', 'Running', 'Terminated') helps visualize the movement of processes through the system. This practice question is designed to help students understand the differences between preemptive and non-preemptive scheduling and how to calculate performance metrics for each.

Loading lesson…