Proportional Allocation

Duration: 4 min

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Module outline

  1. Discrete Mathematics: Permutation, Combination and Probability / क्रमचय, संचय एवं प्रायिकता, Set Theory, Relations, Functions, Propositional and Predicate Logic, Graph Theory, Group Theory
  2. Digital Logic: Digital Systems & Boolean Basics, Boolean Expression, Boolean Minimization, Logic Gates & Hardware, Combinational Circuit, Sequential Circuits, Number System, Number Representation, Floating Point Rep
  3. Computer Organization and Architecture: Basics of COA, Programming the Basic Computer, Cache Memory Organization, Input Output Organisation, Instr Formats & Modes, Register Transfer and Microoperations, Control Unit Design, Pipelining, Multiprocessors
  4. Programming: Language Design, C Fundamentals, Control Flow, Functions, Arrays & Pointers, Storage Classes, Structures & Enums, DMA, Macros, Scoping & File Handling, OOPS with C++
  5. Data Structures: Introduction to DS, Array, Linked List, Stack, Queue, Tree, Graphs, Hashing
  6. Algorithms: Algorithm Analysis, Time Complexity Analysis, Sorting Algorithms, Greedy Algorithms, Dynamic Programming, Minimum Spanning Trees, Shortest Path Algos, Advanced Algorithms
  7. Theory of Computation: Grammar, Regular Language Properties, Moore & Mealy Machines, Turing Machines
  8. Compiler Design: 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, Introduction to TOC, Deterministic FA (DFA), Non-Deterministic FA, Regular Expressions, Pushdown Automata & CFG, Complexity Theory
  9. Operating Systems: Introduction to OS, Process Management, CPU Scheduling, Process Synchronization, Threads & Process Creation, Deadlock, Memory Management, Virtual Memory, Disc Scheduling, File Management, Unix OS, Linux OS, Security
  10. 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, ORDBMS, NoSQL
  11. 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
AI summary & chapters

AI Summary

An AI-generated summary of this video lecture.

This educational video lecture explains the concept of Weighted or Proportional Allocation in operating system memory management. The instructor introduces a specific formula used to distribute physical memory frames among processes based on their relative sizes. The core formula presented is a(i) = s(i) / S x m, where allocation is proportional to the process size. A detailed numerical example is worked through on a digital whiteboard, demonstrating how to calculate the exact number of frames assigned to three distinct processes with sizes of 20k, 30k, and 50k, given a total of 30 available frames.

Chapters

  1. 0:00 – 2:00 00:00-02:00

    The video begins with a slide titled 'Weighted / Proportional Allocation'. The instructor explains that frames are allocated according to the weights of the process. He defines the formula a(i) = s(i) / S x m. He clarifies that a(i) represents the number of allocated frames, s(i) is the size of the specific process, S is the total size of virtual memory (calculated as the sum of all process sizes), and m is the total number of frames available in the system. He sets up an example scenario involving three processes with sizes of 20k, 30k, and 50k, and a total of 30 frames to be allocated.

  2. 2:00 – 4:14 02:00-04:14

    The instructor moves to the whiteboard to solve the example. He writes down the process identifiers P1, P2, and P3 with their respective sizes: 20k, 30k, and 50k. He calculates the total virtual memory size S as 100k (20+30+50). He then calculates the allocation for P1 as (20/100)*30, resulting in 6 frames. He similarly determines that P2 gets 9 frames and P3 gets 15 frames. He draws a diagram labeled '1GB' with a rectangle divided into blocks to visualize the memory structure, circling the final formula to emphasize its importance in the calculation.

The lecture effectively bridges theoretical formulas with practical application. By defining the variables in the proportional allocation formula and then immediately applying them to a concrete example, the instructor demonstrates how larger processes receive a larger share of memory frames. The visual aids, including the written calculations and the memory block diagram, reinforce the concept that allocation is strictly proportional to the process size relative to the total system memory.

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