Job Scheduling Problem

Duration: 7 min

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Inside: a video lesson and guided study material.

Module outline

  1. About Course: About the Course
  2. Section A: General Awareness: Polity, Physics, Biology, Chemistry, Static General Knowledge, History, Geography, Indian Economy, GK- Current Affairs, Evolution of Indian Banking (Banking & Financial Awareness), Environment
  3. Section A: General Intelligence & Reasoning ability: Series (Number and Letter Series) (Numerical Relations and Reasoning), Coding Decoding, Data Sufficiency, Non Verbal Reasoning (Spatial Aptitude) (Spatial Reasoning) (Visual Reasoning), Analytical Reasoning (Counting Figures Reasoning), Blood Relations, Syllogisms, Deductive and Inductive Reasoning (Logical Deduction and Induction) (Prepositional Reasoning), Seating Arrangements, Directions (Direction Test), Puzzle Solving (Puzzles), Calendar, Clock, Cubes & Dices, Selection Decision Table (Decision Making), Logical Sequence Of Words, Crypt Arithmetic, Venn Diagram, Data Arrangement, Inequality, Analogy, Ranking, Order and Sequence, TCS NQT Advanced Reasoning Ability
  4. Section A: Arithmetical & Numerical Ability: Ratio and Proportion (Ratios), Divisibility Rules, Data Interpretation, Mixture and Alligation, Permutation and Combination, Logarithm, Number System, HCF LCM, Sequence and Series (Series), Speed Time and Distance, Percentage, Average, Profit and Loss, Simple Interest and Compound Interest, Time and Work, Pipe and Cistern, Mensuration and Geometry, Powers and Exponents (Surds and Indices), Algebra, Probability, Mental Ability, Age Problems, Partnership, Statistics, Arithmetic, Speed Mathematics and Basic Mathematics, Miscellaneous
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  6. Section A: Hindi Language & Comprehension: भाषा, लिपि, ध्वनि, वर्ण, अक्षर, स्वर, व्यंजन, मात्रा और संयुक्ताक्षर, वर्तनी, वर्ण-विन्यास, अनुस्वार, अनुनासिक, चंद्रबिंदु और ‘र’ के रूप, शब्द, पद और शब्द-भेद, संज्ञा और सर्वनाम, विशेषण और क्रिया, लिंग, वचन, पुरुष और कारक, काल, वाच्य, वाक्य और वाक्य-भेद, संधि, समास, विलोम शब्द, पर्यायवाची शब्द, सामान्य अशुद्धियाँ, अनेक शब्दों के लिए एक शब्द, मुहावरे और लोकोक्तियाँ, अपठित गद्यांश और अपठित पद्यांश, Multi-Topic Content (Cross-Concept Material), वर्णमाला
  7. Section B: 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++, Language Design, Intro to Compilers, Visual Basics, Syntax Analysis: Bottom-Up, Object Oriented Technology
  8. Section B: 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, Mobile Computing, Net Layer:Routing Protocol, Cyber Safety and Security
  9. Section B: 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
  10. Section B: 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
  11. Section B: 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
  12. Section B: 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
  13. Section B: 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
  14. Section B: 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
  15. Section B: Python Language: Introduction to Python, Tokens, Variables, Data Types, I/O, Operators & Expressions, Control Flow & Looping, Collections & Strings, Functions & Modules, File Handling & Data Analysis
  16. Section B: 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
  17. Section B: Design & Analysis of Algorithms: Algorithm Analysis, Time Complexity Analysis, Sorting Algorithms, Greedy Algorithms, Dynamic Programming, Minimum Spanning Trees, Shortest Path Algos, Advanced Algorithms
  18. Section B: Mathematics: Linear Algebra, Calculus, Trigonometry, Vectors, Set Theory, Functions, Relations, Propositional and Predicate Logic, Research Process Steps, Graph Theory
  19. Section B: Computer Graphics, Multimedia & Mobile Computing: Basics of Computer Graphics, 2-D Geometrical Transforms and Viewing, 3-D Object Representation, Geometric Transformations and Viewing, Multimedia
  20. Section B: Emerging Trends: Emerging Tech Trends, Knowledge Representation, Natural Language Processing
  21. DSSSB Previous Year Paper:
  22. 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.

The video lecture introduces the Job Scheduling Problem, a classic optimization problem in computer science. The instructor begins by defining the problem parameters on a slide: a single CPU, non-primitive scheduling, and n-jobs where each job has an arrival time of 0, a burst time of 1, a deadline Di, and a profit Pi. The objective is to select a subset of jobs that can be completed within their deadlines to maximize total profit. A visual chart titled '10X10 Job Shop Scheduling Problem' is displayed to illustrate an unconstrained schedule. The lecture then transitions to a specific numerical example from a GATE 2005 exam question involving 9 tasks (T1 to T9). The instructor demonstrates a greedy algorithm approach, drawing a timeline and filling slots with tasks based on their profits and deadlines to determine the optimal schedule and identify which tasks must be left out.

Chapters

  1. 0:00 – 2:00 00:00-02:00

    The instructor presents the problem definition on a slide titled 'Job scheduling problem'. He highlights key constraints: 'single CPU with Non-Primitive Scheduling and n-jobs'. He specifies that 'arrival time is 0, burst time of each job requirement is 1'. The goal is to 'Select a Subset of 'n' jobs, such that, the jobs in the subset can be completed with in the deadline and generate Max profit.' A chart labeled '10X10 Job Shop Scheduling Problem' shows colored bars representing an 'Unconstrained Schedule'. The instructor underlines 'Non-Primitive Scheduling' and circles 'deadline Di'. He writes 'J1 -> S' on the screen, indicating the mapping of a job to a time slot. The slide also mentions 'Knowledge Gate Educator' and 'Sanchit Jain Sir' in the bottom left corner.

  2. 2:00 – 5:00 02:00-05:00

    The slide changes to a specific problem statement: 'Q. We are given 9 tasks T1, T2... T9.' A table lists tasks, profits, and deadlines. For example, T3 has profit 30 and deadline 5. T1 has profit 15 and deadline 7. The question asks, 'Are all tasks completed in the schedule that gives maximum profit? (Gate-2005) (2 Marks)'. Four options are provided: (A) All tasks are completed, (B) T1 and T6 are left out, (C) T1 and T8 are left out, (D) T4 and T6 are left out. The instructor draws a timeline with 9 boxes labeled 1 through 9. He begins solving by writing 'T3' into slot 3, as it has the highest profit (30) and a deadline of 5. He then writes 'T7' into slot 2 (profit 23, deadline 2).

  3. 5:00 – 6:50 05:00-06:50

    The instructor continues filling the timeline to construct the optimal schedule. He writes 'T9' (profit 25, deadline 3) into slot 1. He places 'T2' (profit 20, deadline 2) into slot 2, but then adjusts. Looking at the final board state, the slots are filled as: Slot 1 with T2, Slot 2 with T7, Slot 3 with T9, Slot 4 with T5, Slot 5 with T3, Slot 6 with T1, and Slot 7 with T8. This arrangement satisfies all deadlines. The tasks T4 and T6 are not placed in any slot. The instructor concludes that T4 and T6 are the tasks left out, corresponding to option (D). The board shows the final schedule clearly.

The lecture effectively bridges theoretical problem definition with practical application. It starts by establishing the constraints of the Job Scheduling Problem, emphasizing the trade-off between deadlines and profits. The instructor then applies a greedy strategy to a concrete example, visually demonstrating how to map tasks to time slots. By sorting tasks by profit and placing them in the latest possible slot before their deadline, he derives the optimal subset of jobs. The final board state clearly shows which tasks are feasible and which are excluded, reinforcing the algorithmic approach to solving scheduling problems.

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