Conclusion of External Fragmentation

Duration: 2 min

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Module outline

  1. Quantitative Ability: Speed Mathematics and Basic Mathematics, Percentage, Ratio and Proportion (Ratios), Average, Profit and Loss, Simple Interest and Compound Interest, Time and Work, Pipe and Cistern, Speed Time and Distance, Number System, HCF LCM, Data Interpretation, Age Problems, Mixture and Alligation, Partnership, Algebra, Sequence and Series (Series), Mensuration and Geometry, Arithmetic
  2. Reasoning Ability: Puzzle Solving (Puzzles), Seating Arrangements, Coding Decoding, Blood Relations, Directions (Direction Test), Syllogisms, Data Sufficiency, Ranking, Order and Sequence, Series (Number and Letter Series) (Numerical Relations and Reasoning), Logical Sequence Of Words, Calendar, Clock, Cubes & Dices, Analytical Reasoning (Counting Figures Reasoning), Data Arrangement, Non Verbal Reasoning (Spatial Aptitude) (Spatial Reasoning) (Visual Reasoning), Deductive and Inductive Reasoning (Logical Deduction and Induction) (Prepositional Reasoning)
  3. Verbal Ability: Comprehension / Reading Comprehension / Unseen Passages (Critical Reasoning) (Paragraph Questions), Cloze Test (Cloze Passage), Sentence Re-arrangements (Para Jumbles) (Narrative Sequencing), Vocabulary, Sentence Completion (Fill in the blanks), Active Passive Voice (Voice), Direct and Indirect Speech, Subject Verb Agreement (Verb Noun Agreement), Tenses, Preposition, Articles, Sentence Correction (Error Correction)
  4. Programming Basics (MCQs + Interview): C Programming by Yash Sir, Programming in C++, Java, Python for Placements by Yash Sir
  5. OOPs (MCQs + Interview): Object Oriented Programming (OOPS)
  6. DBMS (MCQs + Interview): Basics of DBMS, ER Diagram, Relational Model & Functional Dependencies, Keys & Integrity Constraints, Normalization (1NF - BCNF), Transaction Management, Decomposition Properties & 4NF, Concurrency Control, Database Recovery, File Organization & Indexing, Relational Algebra, Database Security & Authorization
  7. SQL (MCQs + Interview): SQL
  8. Operating Systems (MCQs + Interview): Introduction to OS, Process Management, CPU Scheduling, Deadlock, Threads & Process Creation, Memory Management, Virtual Memory, Process Synchronization, Disc Scheduling, File Management, Security
  9. Computer Networks (MCQs + Interview): 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
  10. Coding: Coding Questions by Yash Sir
  11. HR Interview: MR & HR Interview Preparation
AI summary & chapters

AI Summary

An AI-generated summary of this video lecture.

The lecture focuses on methods to resolve external fragmentation in operating systems. The instructor presents two primary solutions: swapping processes to perform compaction and utilizing non-contiguous allocation. The first method involves swapping processes in and out of main memory at fixed intervals to consolidate free memory space, a process known as compaction or defragmentation. However, the instructor notes this is costly in terms of time, especially when the system is running. The second solution proposed is non-contiguous allocation, where a process is divided into parts and allocated to different areas of memory, eliminating the need for contiguous blocks. The instructor uses a whiteboard diagram to illustrate how processes can be split and placed in various memory locations, effectively utilizing fragmented space.

Chapters

  1. 0:00 – 2:00 00:00-02:00

    The instructor introduces solutions to external fragmentation using a slide titled 'How can we solve external fragmentation?'. He discusses swapping processes to create empty memory parts, explicitly mentioning 'Compaction, defragmentation' on the slide. He highlights that this solution is 'very costly in respect to time'. He then transitions to the second solution, 'non-contiguous allocation', explaining that a process can be 'divided into parts and different parts can be allocated in different areas'. He begins drawing a diagram on the whiteboard to visualize memory allocation, drawing a rectangle to represent memory and smaller shapes to represent processes.

  2. 2:00 – 2:25 02:00-02:25

    The instructor continues his explanation of non-contiguous allocation while pointing to the diagram he drew on the whiteboard. He circles a specific section of the memory diagram to emphasize how a process can be split. He reinforces the concept that processes do not need to be in one contiguous block. He gestures towards the diagram, showing how different parts of a process can reside in different areas of memory. This visual aid supports his verbal explanation that non-contiguous allocation solves the fragmentation issue by allowing flexible placement of process parts.

The lecture effectively contrasts two approaches to managing external fragmentation. While compaction is a viable method, its high time cost makes it less ideal for running systems. Non-contiguous allocation emerges as a more efficient alternative, allowing processes to be fragmented and placed in available memory holes. The instructor's use of the whiteboard diagram clarifies the abstract concept of non-contiguous allocation, showing students how memory can be utilized more effectively without requiring large, contiguous blocks.

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