C-Look Scheduling

Duration: 2 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)
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  5. Java (Cluster 1): Java
  6. ANSI SQL MySQL (Cluster 1,2,3): SQL
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  8. Python (Cluster 2): Python for Placements by Yash Sir
  9. Cloud Fundamentals (Cluster 2): Emerging Tech Trends
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  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 educational video provides a detailed explanation of the C-LOOK disk scheduling algorithm, positioning it within the context of other scheduling methods like SCAN, LOOK, and C-SCAN. The lecture begins by defining C-LOOK through on-screen text, stating that it functions similarly to how LOOK relates to SCAN. Specifically, the disk arm in C-LOOK does not travel to the physical end of the disk; instead, it services the last request in the current direction and then jumps to the last request at the other end. This mechanism is designed to prevent extra delays caused by unnecessary traversal to the disk's physical limits. The instructor then breaks down the pros and cons, noting that C-LOOK offers more uniform wait times and better response times compared to LOOK. However, it incurs higher overhead to find the last request and is generally not recommended for high-load scenarios. The visual aids help clarify these abstract concepts for students.

Chapters

  1. 0:00 – 1:55 00:00-01:55

    The instructor starts by reading the definition of C-LOOK from the slide, emphasizing its relationship to C-SCAN. He then draws a diamond-shaped diagram on the whiteboard to visually connect the four algorithms: SCAN, LOOK, C-SCAN, and C-LOOK, illustrating their structural similarities. Following this, he draws a large circle to represent the disk platter and sketches a line inside it to demonstrate the head movement. He points to the "Advantage" section, highlighting that C-LOOK provides more uniform wait times and better response times compared to LOOK. He then moves to the "Disadvantage" section, explaining that the overhead to find the last request and return to the initial position is higher, making it unsuitable for cases with more load. Throughout the video, he uses hand gestures to emphasize the movement of the disk arm and the logic behind the algorithm's efficiency. He specifically underlines the text regarding overhead and load conditions to stress the limitations of the algorithm in heavy usage scenarios.

The lecture effectively bridges the gap between theoretical definitions and practical visualization. By drawing diagrams and referencing specific slide text, the instructor clarifies how C-LOOK optimizes disk access by avoiding full traversals, while also acknowledging the computational cost involved in managing request boundaries.

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