Understanding Page Fault and Page Fault Service

Duration: 7 min

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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: वृद्धि और विकास / Growth and Development, Concept of Pedagogy, विकास के सिद्धांत / Theories of Development, समावेशी शिक्षा / Inclusive Education, Experiential Pedagogy, आकलन और मूल्यांकन / Assessment and Evaluation, समाजीकरण और जेंडर / Socialisation and Gender, National Education Policy (NEP) 2020, संज्ञानात्मक प्रक्रियाएँ / Cognitive Processes, शिक्षण योजना और शिक्षण कौशल / Teaching Planning and Teaching Skills, Personality Development, शिक्षण विधियाँ / Teaching Methods, अधिगम और व्यवहारवादी सिद्धांत / Learning and Behavioural Theories, Learners & Learning Process, Factors Affecting Teaching, शिक्षण विधियाँ एवं उपागम / Teaching Methods and Approaches, शिक्षण-अधिगम प्रक्रिया एवं कक्षा प्रबंधन / Teaching-Learning Process and Classroom Management, शिक्षण सहायक सामग्री एवं शैक्षिक तकनीकी / Teaching Aids and Educational Technology, सूक्ष्म शिक्षण एवं कक्षा संप्रेषण / Microteaching and Classroom Communication, आकलन एवं मूल्यांकन / Assessment and Evaluation, पाठ्यचर्या, कला एवं सह-शैक्षिक क्षेत्र / Curriculum, Arts and Co-curricular Areas, दिव्यांग बच्चों की शिक्षा / Education of Children with Disabilities, शिक्षक: गुण, व्यावसायिक नैतिकता एवं विकास / Teacher: Qualities, Professional Ethics and Development
  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, कंप्यूटर के मूल सिद्धांत / Computer Fundamentals, साइबर सुरक्षा / Cyber Safety and Security, कंप्यूटर सॉफ़्टवेयर / Computer Software, ऑपरेटिंग सिस्टम / Operating System, वर्ड प्रोसेसिंग (MS Word) / Word Processing (MS Word), कंप्यूटर नेटवर्क / Computer Networks, प्रेज़ेंटेशन (MS PowerPoint) / Presentation Software (MS PowerPoint)
  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, समुच्चय, संबंध, फलन और विविक्त गणित / Sets, Relations, Functions and Discrete Mathematics, संख्या पद्धति और संख्या सिद्धांत / Number Systems and Number Theory, यूक्लिडीय ज्यामिति और क्षेत्रमिति / Euclidean Geometry and Mensuration, सांख्यिकी और प्रायिकता / Statistics and Probability, निर्देशांक ज्यामिति, सदिश और त्रिविमीय ज्यामिति / Coordinate Geometry, Vectors and 3D Geometry, बहुपद, समीकरण और सम्मिश्र संख्याएँ / Polynomials, Equations and Complex Numbers, समतल क्षेत्रमिति / Plane Mensuration, प्रतिचयन / Sampling, प्रतिशत / Percentage, सरलीकरण, घातांक और करणी / Simplification, Indices and Surds, अनुपात और समानुपात / Ratio and Proportion
  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, व्यापार, विपणन एवं उपभोक्ता संरक्षण / Trade, Marketing and Consumer Protection
  16. Statistical Techniques: Probability, Statistics
  17. Interpolation - DI: आँकड़ा निर्वचन / Data Interpretation
  18. Basis of Physics: वैज्ञानिक उपलब्धियाँ और अनुसंधान / Scientific Achievements and Research
  19. Previous Year Paper:
  20. Business Studies and Management: Business Communication, प्रबंध के सिद्धांत एवं कार्य / Principles and Functions of Management, लेखांकन के आधार एवं लेन-देनों का अभिलेखन / Accounting Fundamentals and Recording of Transactions, Business Economics, ह्रास, अंतिम खाते व कंप्यूटरीकृत लेखांकन / Depreciation, Final Accounts and Computerised Accounting, Knowledge Management & New Economy
AI summary & chapters

AI Summary

An AI-generated summary of this video lecture.

The lecture covers fundamental concepts of virtual memory management, specifically focusing on demand paging and page fault handling. The instructor begins by explaining that pages are loaded into main memory only when needed, which optimizes memory usage and reduces swap time. He introduces the valid-invalid bit scheme used by hardware to distinguish between pages currently in memory and those on disk. The session transitions to page faults, defining them as occurrences when a process accesses a page not in main memory. The instructor details the steps to handle these faults, including checking reference validity, finding free frames, and scheduling disk reads, supported by a flowchart diagram.

Chapters

  1. 0:00 – 2:00 00:00-02:00

    The video opens with a slide titled 'Basic Concepts' and the 'KG' logo. The on-screen text explains that when a process starts, no page is loaded into main memory before demand, avoiding unnecessary reads and decreasing swap time. The instructor points to a diagram showing 'logical memory' with pages 0-7 labeled A-H. Next to it is a 'page table' with columns for 'frame' and 'valid-invalid bit'. He explains that hardware is needed to distinguish pages in memory from those not in memory, introducing the valid-invalid bit scheme. He points to the 'physical memory' column on the right, showing frames 0-15, and a cylinder representing secondary storage containing pages A-H. He writes 'SM' (Secondary Memory) next to the cylinder.

  2. 2:00 – 5:00 02:00-05:00

    The instructor continues analyzing the page table. He points to row 0, showing Page A maps to Frame 4 with a valid bit 'v'. He moves to row 3, showing Page D maps to Frame 3 with an invalid bit 'i', indicating Page D is not in physical memory. He highlights row 5, where Page F maps to Frame 9 with a valid bit 'v', and points to Frame 9 in the physical memory list which contains 'F'. He contrasts this with the disk, where 'F' is also stored. He emphasizes that the valid bit tells the system if a page is resident in RAM. If the bit is 'i', the page is on disk. He circles the 'F' in the page table and points to the corresponding frame in physical memory to reinforce the mapping. He also points to the empty frames in physical memory (e.g., frame 0, 1, 2, 5, 6, 7, 8, 10-15) to show available space.

  3. 5:00 – 7:16 05:00-07:16

    The slide changes to 'Page Fault'. The text defines a page fault as occurring when a process tries to access a page not in main memory. The instructor lists steps to handle this: if the reference is invalid, terminate the process; if valid but not in memory, page it in. He points to the text 'We find a free frame' and 'We schedule a disk operation'. A flowchart diagram illustrates the process: (1) Reference, (2) Trap, (3) Page on backing store, (4) Bring in missing page, (5) Free frame, (6) Restart instruction. He points to each numbered step in the diagram, explaining the flow from the initial memory reference to the trap handler, finding a free frame, reading the page from disk, and restarting the instruction. He gestures with his hands to emphasize the steps.

The lesson progresses from the basic mechanism of demand paging using valid-invalid bits to the specific handling of page faults. It establishes that pages are loaded on demand to save memory, managed via a page table. When a page is accessed but not in memory (indicated by an invalid bit), a page fault occurs. The system then handles this by checking validity, finding a free frame, reading the page from disk, and restarting the instruction, ensuring efficient memory management.

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