Multiprogramming OS

Duration: 6 min

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Module outline

  1. Communication Round: Vocabulary, Subject Verb Agreement (Verb Noun Agreement), 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), Direct and Indirect Speech, Active Passive Voice (Voice), Verbal Analogy (Word Based Analogy), Articles, Preposition, Conjunction, Sentence Construction, English Writing Ability, Communication Assessment
  2. Quantitative Aptitude: Ratio and Proportion (Ratios), Divisibility Rules, Data Interpretation, Mixture and Alligation, Permutation and Combination, Logarithm, Number System, HCF LCM, Speed Time and Distance, Percentage, Average, Powers and Exponents (Surds and Indices), Time and Work, Mensuration and Geometry, Age Problems, Pipe and Cistern, Probability, Profit and Loss, Simple Interest and Compound Interest, Algebra
  3. Analytical and Logical Reasoning: Series (Number and Letter Series) (Numerical Relations and Reasoning), Coding Decoding, Data Sufficiency, Non Verbal Reasoning (Spatial Aptitude) (Spatial Reasoning) (Visual Reasoning), Directions (Direction Test), Ranking, Order and Sequence, Deductive and Inductive Reasoning (Logical Deduction and Induction) (Prepositional Reasoning), Selection Decision Table (Decision Making), Logical Sequence Of Words, Puzzle Solving (Puzzles), Syllogisms, Seating Arrangements, Calendar, Clock, Blood Relations, Cubes & Dices, Venn Diagram, Analytical Reasoning (Counting Figures Reasoning)
  4. Cognizant Gaming Aptitude: Gamified / Game Based Aptitude
  5. Java (Cluster 1): Java
  6. ANSI SQL MySQL (Cluster 1,2,3): SQL
  7. HTML, CSS, JavaScript (Cluster 1,3): HTML, CSS, JavaScript
  8. Python (Cluster 2): Python for Placements by Yash Sir
  9. Cloud Fundamentals (Cluster 2): Emerging Tech Trends
  10. C# (Cluster 3): C#
  11. OOPs: Object Oriented Programming (OOPS)
  12. Technical Assessment (Coding): Coding Questions by Yash Sir, C Programming by Yash Sir, Programming in C++, Pseudo Codes
  13. Data Structures: Introduction to DS, Array, Stack, Queue, Linked List, Tree, Graphs, Hashing
  14. DBMS: 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
  15. Operating Systems: 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
  16. 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, Hardware basics, Network Security, Mobile Technology, Cloud Computing and IoT, Cyber and Info Security
AI summary & chapters

AI Summary

An AI-generated summary of this video lecture.

This lecture introduces multiprogramming operating systems, explaining how keeping multiple jobs in main memory prevents CPU idling. The instructor uses a recurring diagram showing secondary disk storage, main memory holding the operating system and Jobs A, B, and C, and a CPU box. Key points include that a single program cannot keep the CPU or I/O devices busy at all times, so jobs are initially kept in a disk job pool and loaded into memory. When one job waits for I/O, the OS switches to another executable job, ensuring high CPU utilization. The lecture concludes by noting the advantage of efficient CPU use and the disadvantage of complicated scheduling.

Chapters

  1. 0:00 – 2:00 00:00-02:00

    The instructor presents a slide titled 'Multiprogramming Operating System' with a diagram showing secondary disk storage, main memory containing the operating system and Jobs A, B, and C (with Job C waiting for CPU), and a separate CPU box. Arrows labeled 'Writing output data' and 'Execution in progress' connect these components. The instructor gestures toward the diagram while red handwritten annotations appear at the bottom of the frame.

  2. 2:00 – 5:00 02:00-05:00

    The lecture explains that a single program cannot keep the CPU or I/O devices busy at all times, so multiprogramming keeps several jobs in main memory simultaneously. Jobs are initially stored on disk in a job pool before being allocated to memory. The instructor points to specific components like 'Job C (Waiting for CPU)' and draws a red circle around 'Job A' to illustrate the waiting state. A handwritten Hindi note appears stating that the processor will not wait for anyone.

  3. 5:00 – 6:29 05:00-06:29

    The final slide states that in a multi-programmed system, the operating system simply switches to and executes another job so the CPU is never idle. The same diagram of disk storage, main memory with multiple jobs, and CPU is shown again. A later slide lists the advantage as high and efficient CPU utilization, and the disadvantage as being difficult to program due to complicated schedule handling.

The lecture builds a clear conceptual model of multiprogramming: because individual programs alternate between CPU execution and I/O waiting, a single program leaves the processor idle. By loading several jobs into main memory from a disk job pool, the OS can switch to another ready job whenever one blocks on I/O. The recurring diagram reinforces this by showing the OS, multiple jobs (one explicitly waiting), and the CPU as distinct but connected components. The instructor emphasizes that the processor never waits, using both English slide text and a Hindi annotation to drive home this point. The lesson closes by balancing the benefit—high CPU utilization—against the cost of more complex scheduling and programming.

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