Journals in Linux
Duration: 5 min
This video lesson is available to enrolled students.
Inside: a video lesson and guided study material.
Module outline
- Course Overview: About the Course
- Paper - 1 | Unit - 1 | Teaching Aptitude: Nature, Objectives & Characteristics of Teaching, Learners & Learning Process, Factors Affecting Teaching, Methods of Teaching, Teaching-Learning Aids & ICT Integration, Evaluation, Assessment & Measurement
- Paper - 1 | Unit - 2 | Research Aptitude: Introduction to Research, Validity & Reliability, Research Paradigms & Types of Research, Research Process Steps, Research Ethics, Writing & Publication
- Paper - 1 | Unit - 3 | Comprehension: Comprehension / Reading Comprehension / Unseen Passages (Critical Reasoning) (Paragraph Questions)
- Paper - 1 | Unit - 4 | Communication: Communication Basics, Language and Semiotics, Types of Communication, Communication Models, Mass Communication, Mass Media, Journalism, General Knowledge and General Studies related to Communication
- Paper - 1 | Unit - 5 | Mathematical Reasoning and Aptitude: Series (Number and Letter Series) (Numerical Relations and Reasoning), Coding Decoding, Number System, Percentage, Ratio and Proportion (Ratios), Simple Interest and Compound Interest, Speed Time and Distance, Powers and Exponents (Surds and Indices), Profit and Loss, Average, Blood Relations, Directions (Direction Test), Analytical Reasoning (Counting Figures Reasoning), Verbal Analogy (Word Based Analogy), Divisibility Rules, Calendar, Miscellaneous, Time and Work, Algebra
- Paper - 1 | Unit - 6 | Logical Reasoning: Syllogisms, Non Verbal Reasoning (Spatial Aptitude) (Spatial Reasoning) (Visual Reasoning), Deductive and Inductive Reasoning (Logical Deduction and Induction) (Prepositional Reasoning), Venn Diagram, School Of Thoughts, Fallacy, Western Logic
- Paper - 1 | Unit - 7 | Data Interpretation: Data Interpretation
- Paper - 1 | Unit - 8 | Information and Communication Technology: MS Office Applications, Cyber Threats and Malware Attacks, Role of Internet and Web Services, Electronic Data Interchange and E-Commerce, Internet Fundamentals, Web Design & Development, Web Publishing & Hosting, Emerging Technologies, Terms & Abbreviations, Artificial Intelligence, Society, Law & Ethics, Keyboard Shortcuts, Website, Browser & Services
- Paper - 1 | Unit - 9 | People Development and Environment: Ecosystem, Biomes & Environmental Issues, MDG & SDG, Air Pollution, Water Pollution, Soil, Noise Pollution and Waste Management, Natural Resources, Energy & Disaster Management, Global Environmental Conventions – COP, Protocols & ISA
- Paper - 1 | Unit - 10 | Higher Education System: Vedic Education, Jainism & Buddhism, Ancient Universities, Pre-Independence Commissions, Post-Independence Policy, Higher Education Structure & Accreditation, Universities & Learning Programmes, Types of Education & NEP 2020
- Paper 2 | Unit 1 | Discrete Structures and Optimization: Propositional and Predicate Logic, Set Theory, Relations, Functions, Permutation and Combination, Probability, Graph Theory, Group Theory, Digital Systems & Boolean Basics, Boolean Expression, Boolean Minimization, Optimization
- Paper 2 | Unit 2 | Computer System Architecture: Logic Gates & Hardware, Combinational Circuit, Sequential Circuits, Number System, Number Representation, Floating Point Rep, Basics of COA, Register Transfer and Microoperations, Programming the Basic Computer, Instr Formats & Modes, Control Unit Design, Pipelining, Input Output Organisation, Cache Memory Organization, Multiprocessors
- Paper 2 | Unit 3 | Programming Languages and Computer Graphics: Language Design, C Fundamentals, Control Flow, Functions, Arrays & Pointers, Storage Classes, Structures & Enums, DMA, Macros, Scoping & File Handling, HTML Basics, XML, JavaScript-Basics, Java, Basics of Computer Graphics, 2-D Geometrical Transforms and Viewing, 3-D Object Representation, Geometric Transformations and Viewing, OOPS with C++, Java Fundamentals
- Paper 2 | Unit 4 | Database Management Systems: Basics of DBMS, ER Diagram, Relational Model & Functional Dependencies, Keys & Integrity Constraints, Normalization (1NF - BCNF), Decomposition Properties & 4NF, File Organization & Indexing, Relational Algebra, SQL, 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
- Paper 2 | Unit 5 | System Software and Operating System: Introduction to OS, Process Management, CPU Scheduling, Process Synchronization, Threads & Process Creation, Deadlock, Memory Management, Virtual Memory, Disc Scheduling, File Management, Windows OS, Linux OS, Security, Distributed Systems, Virtual Machines
- Paper 2 | Unit 6 | Software Engineering: Fundamentals of Software Engineering, Software Requirements and Quality Assurance, Software Design, Estimation and Metrics, Software Testing, Software Maintenance and Configuration Management
- Paper 2 | Unit 7 | Data Structures and Algorithms: Introduction to DS, Array, Stack, Queue, Linked List, Tree, Graphs, Hashing, Algorithm Analysis, Time Complexity Analysis, Sorting Algorithms, Greedy Algorithms, Dynamic Programming, Minimum Spanning Trees, Shortest Path Algos, Advanced Algorithms
- Paper 2 | Unit 8 | Theory of Computation and Compilers: Introduction to TOC, Deterministic FA (DFA), Non-Deterministic FA, Regular Expressions, Grammar, Regular Language Properties, Moore & Mealy Machines, Pushdown Automata & CFG, Turing Machines, Complexity Theory, Intro to Compilers, Lexical Analysis, Grammar & CFG, Syntax Analysis: Top-Down, Syntax Analysis: Bottom-Up, Semantic Analysis & SDT, Intermediate Code Gen, Code Optimization, Run Time Environment
- Paper 2 | Unit 9 | Data Communication and 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, Cloud Computing
- Paper 2 | Unit 10 | Artificial Intelligence: Approaches to AI, Search Algorithms, Game Playing, Knowledge Representation, Planning, Multi Agent Systems, Fuzzy Sets, Natural Language Processing, Artificial Neural Networks, Genetic Algorithms
- Live Classes: NTA UGC NET 2025 Live Class
- Paper 1 | Full Mock Tests:
- Paper 2 | Full Mock Tests:
- Paper 1 | Previous Year Papers:
- Paper 2 | Previous Year Papers:
AI summary & chapters
AI Summary
An AI-generated summary of this video lecture.
This lecture introduces journaling in Linux file systems as a reliability mechanism. The instructor defines a journal as a special log that records file system changes before they are permanently saved to disk. The motivation is explained through a power-failure scenario during a file copy: without journaling, files may become corrupted or inconsistent, whereas with journaling, recovery becomes faster and safer. The lesson then moves to how journaling works, presenting a three-step transaction process: Step 1 records the change in the journal, Step 2 writes the actual change to the file system, and Step 3 marks the journal entry as completed. A concrete example uses creating a file named report.txt, where Linux first records the operation in the journal, then creates the file on disk, and finally marks the journal entry complete. The instructor emphasizes that if power fails during Step 2, the journal detects the incomplete transaction and Linux can recover automatically. Visual cues include red underlines on the definition and step labels such as Journal Entry Created, Data Written to Disk, and Transaction Completed.
Chapters
0:00 – 2:00 00:00-02:00
The opening slide, titled 'Journaling in Linux File System,' defines journaling as a technique that maintains a special log before actual changes are written to disk. The on-screen text states, 'A Journal records file system changes before they are permanently saved to disk.' The instructor uses a power-failure scenario during a file copy to explain why journaling is needed, contrasting 'Without journaling: Files may become corrupted' with 'With journaling: Recovery becomes faster and safer.' Red underlines are drawn on the definition to emphasize the core idea, and the instructor gestures to highlight the difference between unsafe and safe recovery outcomes.
2:00 – 5:00 02:00-05:00
The lecture transitions to 'How Journaling Works?' and presents a three-step process. Step 1: 'A change is first recorded in the Journal,' labeled 'Journal Entry Created.' Step 2: 'The actual change is written to the file system,' labeled 'Data Written to Disk.' Step 3: 'The journal entry is marked as completed,' labeled 'Transaction Completed.' The instructor illustrates this with the example of creating a file named report.txt, where Linux performs: 1. Record operation in Journal, 2. Create file on disk, 3. Mark Journal entry complete. The slide also notes that if power fails during Step 2, the journal detects the incomplete transaction and Linux can recover automatically, reinforcing the safety benefit introduced earlier.
The central teaching idea is that journaling improves Linux file system reliability by logging changes before committing them to disk. The lesson progresses from definition to motivation to mechanism: first defining a journal as a pre-commit log, then using a power-failure example to show the risk of corruption without it, and finally explaining the three-step transaction sequence. The report.txt example makes the abstract process concrete by mapping each step to a visible operation. The key exam-relevant point is the recovery behavior: an incomplete transaction detected in the journal allows Linux to restore consistency automatically after a crash. Minor details include the slide labels Journal Entry Created, Data Written to Disk, and Transaction Completed, which help students remember the order of operations.