Model of Threading
Duration: 3 min
This video lesson is available to enrolled students.
Inside: a video lesson and guided study material.
Module outline
- About Course: About the Course
- CS | 01 | Digital Logic and Circuits and Discrete Mathematical Structures: Digital Systems & Boolean Basics, Number System, Number Representation, Logic Gates & Hardware, Boolean Expression, Boolean Minimization, Combinational Circuit, Sequential Circuits, Set Theory, Relations, Functions, Graph Theory, Group Theory, Propositional and Predicate Logic, Permutation and Combination
- CS | 02 | Computer Organization and Architecture: Basics of COA, Cache Memory Organization, Input Output Organisation, Pipelining, Instr Formats & Modes, Control Unit Design, Multiprocessors
- CS | 03 | Data Structures and Algorithm: 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, Complexity Theory, Advanced Algorithms
- CS | 04 | Problem Solving through C Programming: C Fundamentals, Control Flow, Functions, Arrays & Pointers, Storage Classes, Structures & Enums, DMA, Macros, Scoping & File Handling
- CS | 05 | Object Oriented Techniques: Object Oriented Technology, Java
- CS | 06 | 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, Unix OS
- CS | 07 | Database Management Systems: Basics of DBMS, ER Diagram, Relational Model & Functional Dependencies, Keys & Integrity Constraints, Normalization (1NF - BCNF), Decomposition Properties & 4NF, Relational Algebra, SQL, Relational Calculus, Transaction Management, Concurrency Control, Database Recovery, Database Security & Authorization, Query Processing & Optimization, File Organization & Indexing
- CS | 08 | 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
- CS | 09 | Software Engineering: Fundamentals of Software Engineering, Software Requirements and Quality Assurance, Software Design, Estimation and Metrics, Software Testing, Software Maintenance and Configuration Management
- CS | 10 | Internet Technology, Web Design and Web Technology: Internet Fundamentals, Web Design & Development, Protocols & Services, Web Publishing & Hosting, Server Side & Security, Emerging Technologies, JavaScript-Basics, HTML Basics
- CS | 11 | System Analysis And Design: Fundamentals of Systems and Information Systems, SDLC and Development Approaches, Software Documentation and Software Requirements Specification (SRS), SDD and Quality Assurance, Security, Risk Management & Maintenance
- CS | 12 | Information Security and Cyber Laws: Cyber Threats and Malware Attacks, Role of Internet and Web Services, Security in Mobile and Wireless Computing, Electronic Data Interchange and E-Commerce, Physical Security and Cryptography Basics, Intrusion Detection Systems (IDS), Cyber Safety and Security
- CS | 13 | Computer Graphics: Basics of Computer Graphics, 2-D Geometrical Transforms and Viewing, 3-D Object Representation, Geometric Transformations and Viewing
- GS Paper | 01 | Indian and World Geography: Geography
- GS Paper | 02 | History: History
- GS Paper | 03 | Indian Economy & Social Development: Indian Economy
- GS Paper | 04 | General Science: Biology, Chemistry, Physics
- GS Paper | 05 | Elementary Maths: Number System, Divisibility Rules, HCF LCM, Percentage, Profit and Loss, Simple Interest and Compound Interest, Ratio and Proportion (Ratios), Average, Time and Work, Speed Time and Distance, Algebra, Mensuration and Geometry, Data Interpretation, Arithmetic, Statistics, Probability, Sequence and Series (Series), Mixture and Alligation, Calculus, Trigonometry, Vectors
- GS Paper | 06 | Indian Polity and Governance: Polity
- GS Paper | 07 | Current Events: GK- Current Affairs
- UPLT Live Classes Notes: UPLT Live Classes
- UPLT Full Mock Tests Tier 1:
- UPLT Full Mock Tests Tier 2:
AI summary & chapters
AI Summary
An AI-generated summary of this video lecture.
The lecture introduces the concept of multithreading models, specifically distinguishing between user threads and kernel threads. It details the Many-to-One model, highlighting its limitations regarding blocking calls and CPU utilization. The presentation then transitions to the One-to-One model, explaining its advantages in concurrency and overhead trade-offs. Finally, it covers the Many-to-Many model as a hybrid approach combining the best features of the previous two.
Chapters
0:00 – 2:00 00:00-02:00
The lecture begins with a slide titled "Multithreading Models," defining user threads as application-level and kernel threads as OS-supported. The focus shifts to the "Many-To-One Model," where many user-level threads are mapped onto a single kernel thread. A diagram illustrates this with multiple wavy lines connecting to one 'k'. The instructor explains that if a blocking system call occurs, the entire process blocks, even if other threads could continue. He writes "T1L" and "T2L" on the diagram to label specific user threads and "P1" to denote the process. He notes that because a single kernel thread operates on only one CPU, this model cannot split processes across multiple CPUs. He mentions Green threads for Solaris as a historical example.
2:00 – 3:14 02:00-03:14
The presentation transitions to the "One-To-One Model," creating a separate kernel thread for each user thread. The diagram changes to show four distinct 'k' circles, each linked to a wavy line. The instructor highlights that this model overcomes blocking system call issues and allows splitting across multiple CPUs. However, he points out the significant overhead involved in managing these threads. He cites Linux and Windows 95 to XP as implementations. The final segment introduces the "Many-To-Many Model," which multiplexes user threads onto an equal or smaller number of kernel threads. The diagram shows multiple user threads mapping to three kernel threads. This approach combines the best features of previous models, allowing variable allocation of kernel threads based on CPU count.
The lecture provides a comprehensive overview of multithreading architectures. It starts by establishing the fundamental difference between user and kernel threads. The Many-to-One model is critiqued for its inability to handle parallelism and blocking calls effectively. The One-to-One model is presented as a robust alternative that enables true parallelism but suffers from high overhead. Finally, the Many-to-Many model is described as a hybrid solution that balances flexibility and performance by allowing the kernel to manage a pool of threads for user-level execution efficiently and effectively. This progression illustrates the evolution of threading strategies to optimize system performance and resource management.