Practice Question

Duration: 17 min

This video lesson is available to enrolled students.

Return to /learn/DSSSB-TGT-COMPUTER-SCIENCE-PAPER-2/operating-system/cpu-scheduling/priority-scheduling/asset-practice-question-3685 after enrolling

Inside: a video lesson and guided study material.

Module outline

  1. About Course: About the Course
  2. Programming, Data Structures, OOP & Java: 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, Java, OOPS with C++, Java Fundamentals, Array, String, IO & References, Language Design, Intro to Compilers, Visual Basics, Syntax Analysis: Bottom-Up, Object Oriented Technology
  3. Computer Networks, TCP/IP & Network Security: Introduction to CN, Data Communication, DLL: Flow Control, DLL: Access Control, DLL: Error Control, Data Link Layer - Ethernet, Net Layer: IPv4 & Proto, Net Layer: IP Addressing, Transport Layer Services, TL: Congestion & UDP, Application Layer, Hardware basics, Network Access Technologies, Network Security, Society, Law & Ethics, Cloud Computing, Mobile Computing, Net Layer:Routing Protocol, Cyber Safety and Security
  4. Teaching Methodology: Child Development, Concept of Pedagogy, Theories, Inclusive Education, Experiential Pedagogy, Assessment & Evaluation, Curriculum Framework & Reforms, National Education Policy (NEP) 2020, Psychology, Teaching-Learning Process, Personality Development, Teaching Methods & Strategies, Learning and Motivation, Learners & Learning Process, Factors Affecting Teaching, Methods of Teaching, Nature, Objectives & Characteristics of Teaching, Teaching-Learning Aids & ICT Integration, Classroom Management & Communication, Evaluation, Assessment & Measurement, Curriculum & School Environment, Inclusive Education & Special Needs, Professional Development & Ethics
  5. Digital Electronics / Boolean Logic: Digital Systems & Boolean Basics, Logic Gates & Hardware, Boolean Expression, Boolean Minimization, Combinational Circuit, Sequential Circuits, Number System, Number Representation, Analog-Digital Conversion
  6. Operating Systems & Linux: Introduction to OS, Process Management, CPU Scheduling, Process Synchronization, Threads & Process Creation, Deadlock, Memory Management, Virtual Memory, File Management, Disc Scheduling, Unix OS, Linux OS, Distributed Systems, Windows OS
  7. Data Base Management System: Basics of DBMS, ER Diagram, Relational Model & Functional Dependencies, Keys & Integrity Constraints, Normalization (1NF - BCNF), Decomposition Properties & 4NF, Relational Algebra, SQL, File Organization & Indexing, Transaction Management, Concurrency Control, Database Security & Authorization, Database Recovery, Data Warehousing & Mining
  8. Internet & Web Technologies: Website, Browser & Services, Internet Fundamentals, Web Design & Development, Protocols & Services, Web Publishing & Hosting, Server Side & Security, HTML Basics, CSS, Emerging Technologies, JavaScript-Basics, .Net Programming, Electronic Data Interchange and E-Commerce, XML
  9. Computer Fundamentals, IT Basics & Architecture: Basics of COA, Cache Memory Organization, Input Output Organisation, Register Transfer and Microoperations, Control Unit Design, Programming the Basic Computer, Terms & Abbreviations, MS Office Applications, Instr Formats & Modes, Floating Point Rep
  10. Python Language: Introduction to Python, Tokens, Variables, Data Types, I/O, Operators & Expressions, Control Flow & Looping, Collections & Strings, Functions & Modules, File Handling & Data Analysis
  11. Software Engineering: Fundamentals of Software Engineering, Software Requirements and Quality Assurance, Software Design, Estimation and Metrics, Software Testing, Software Maintenance and Configuration Management, extras, Fundamentals of Systems and Information Systems
  12. Design & Analysis of Algorithms: Algorithm Analysis, Time Complexity Analysis, Sorting Algorithms, Greedy Algorithms, Dynamic Programming, Minimum Spanning Trees, Shortest Path Algos, Advanced Algorithms
  13. Mathematics - I, II, III, IV: Permutation and Combination, Logarithm, Linear Algebra, Algebra, Calculus, Trigonometry, Vectors, Set Theory, Functions, Relations, Propositional and Predicate Logic, Research Process Steps, Graph Theory
  14. Computer Graphics, Multimedia & Mobile Computing: Basics of Computer Graphics, 2-D Geometrical Transforms and Viewing, 3-D Object Representation, Geometric Transformations and Viewing, Multimedia
  15. Emerging Trends: Emerging Tech Trends, Knowledge Representation, Natural Language Processing
  16. Statistical Techniques: Probability, Statistics
  17. Interpolation - DI: Data Interpretation
  18. Basis of Physics: Physics
  19. Previous Year Paper:
  20. Business Studies and Management: Business Communication, Business Organization and Management, Financial Accounting, Business Economics, Management Information System (MIS), Knowledge Management & New Economy
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…