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Teaching on Software

Types of Operating Systems

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Types of Operating Systems There are different types of operating systems, including: Batch Operating System (OS) Multiprogramming Operating System (OS) Time-Sharing OS Multiprocessing OS Distributed OS Network OS Real Time OS Embedded OS  Batch Operating System It doesn’t let users interact directly with the computer. Instead, an operator groups similar jobs together into batches based on their requirements. This system is designed to handle and execute large numbers of jobs well by processing them in these groups. Users prepare their jobs on offline devices like punch cards and submit them to the operator, who then organizes and processes the jobs in batches. Advantages of Batch Operating System: Multiple users can share the system. The system has minimal idle time. It’s efficient for managing and processing large, repetitive tasks. Processors know how long a job will take when it’s in the queue. Disadvantages of Batch Operating System: Batch systems are difficult to debug. They ...

Memory Management in Operating System

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  What is Main Memory  Main memory, also called RAM, is where a computer keeps data and programs that the CPU is currently using. It’s fast and temporary; data is lost when the power is off. What is Memory Management  Memory management is how an operating system handles memory for different programs. It makes sure memory is used efficiently and helps avoid problems like memory waste or fragmentation. Why It's Needed : Allocates memory before processes start and frees it afterward. Keeps track of which memory is used. Reduces memory waste (fragmentation). Ensures memory is used effectively and data stays safe during processing. Logical vs. Physical Address: Logical Address: The address made by the CPU, which can change. Physical Address: The actual address in memory, which stays the same. Static vs. Dynamic Loading: Static Loading: Loads the whole program at once, using more memory. Dynamic Loading: Only loads parts of the program when needed, saving memory. Watch this...

The Structures of Directory in Operating System

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Structures of Directory in Operating System A directory is like a folder that helps organize files on a computer. It arranges files in a clear order, making it easy to find and manage them. There are different types of directory structures in an operating system, each with its own way of organizing files: Single-Level Directory Two-Level Directory Tree Structure/Hierarchical Structure Acyclic Graph Structure General-Graph Directory Structure Single-Level Directory: A single-level directory is the simplest way to organize files. All files are stored in one directory, making it easy to manage and understand. However, if there are many files or multiple users, it can be hard to keep track of everything since every file needs a unique name. Advantages: Easy to set up and use. Quick file searching when there are few files. Simple operations like creating, finding, and deleting files. Disadvantages: Files can accidentally have the same name, causing conflicts. Searching becomes slow with lot...

Mainframe Operating System

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What is a Mainframe Operating System Mainframe operating systems are powerful and widely used in large organizations like banks, governments, and educational institutions. Mainframe operating systems started in the 1940s. IBM became a key player in the 1950s, making mainframes more accessible. A big change came with IBM System/360. In the 1980s, IBM added new features, and in the 2000s, they introduced IBM z/OS and IBM z/VSE. Types of Mainframe OS IBM Z/VM: This system supports virtualization, allowing thousands of servers to run on a single IBM Z server. It offers efficiency, flexibility, easy upgrades, and is good for testing software. IBM Z/VSE: Designed for smaller mainframes, it supports batch and transaction processing. It's ideal for firms with fewer transactions and smaller needs. Linux: An open-source OS that runs on IBM Z, offering high performance. It works well in hybrid cloud setups and supports Linux applications. Advantages of   Mainframe OS High processing powe...

Virtual Memory in Operating System

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 What is Virtual Memory Virtual memory is a technique that makes it seem like there is more memory available than what actually exists. It lets programs use more memory than the computer’s physical memory (RAM) by using part of the storage (like a hard drive) as if it were RAM. This helps run bigger applications on computers with less physical memory. There are two main types of virtual memory: Virtual memory in a computer is managed by the Memory Management Unit (MMU), which converts virtual addresses into physical ones. Paging Memory is divided into small, fixed-size blocks called pages. When RAM is full, pages not in use are moved to the hard drive (swap file). When needed again, they are swapped back into RAM. Segmentation: Memory is divided into segments of different sizes. Segments not needed are moved to the hard drive. The system tracks these segments and brings them back when needed. Sometimes, both paging and segmentation are combined. Virtual Memory vs. Physical Memory:...