Computer systems, Operating systems, Hardware components, Memory management and File Systems

WK01 C229 Cloud Computing Essentials

What are the four major functions of a computer system as described in the material?

The four major functions are

1. Input (gets data from users),

2. Processing (acts on user data),

3. Output (produces data), and

4. Storage (stores data).

Name the three basic components found inside a Central Processing Unit (CPU).

The three basic components inside a CPU are the

1. Arithmetic-Logic Unit (ALU),

2. the Control Unit, and

3. CPU Registers.

Explain the difference between a single-core and a multi-core processor.

A single-core processor performs one operation at a time, rapidly switching between tasks, while a multi-core processor has multiple CPUs on a single chip that can execute multiple operations simultaneously.

What is the purpose of a CPU cache?

A CPU cache is a small, fast memory used by the CPU to reduce the time it takes to access data from main memory (RAM) by storing copies of frequently used data.

What is virtual memory, and how does it help overcome physical memory limitations?

Virtual memory is a memory management technique that uses virtual addresses mapped to both primary memory and secondary storage to give the impression of having a very large memory per process, allowing programs larger than physical memory to execute.

Describe the main function of a device driver.

A device driver acts as a bridge between the operating system and hardware, translating device-specific commands into commands understood by the operating system and vice versa.

What is the difference between a data bus and an address bus?

A data bus is bidirectional and carries data between the processor and other components, while an address bus is unidirectional and carries information about the location of data in memory.

What is the primary function of a file system?

A file system controls how data is stored and retrieved on a storage device, provides access control (like read/write permissions), and stores metadata (like file creation time).

Briefly explain the purpose of disk partitioning.

Disk partitioning divides a storage device into multiple logical storage units (partitions), which can have dedicated areas for specific purposes like the operating system, user data, paging/swapping, cache, and log files.

What is the Master Boot Record (MBR), and what role does it play in the boot process?

The Master Boot Record (MBR) is information in the first sector of a hard disk that identifies how and where an operating system is located so it can be loaded into memory (booted). The basic input/output system (BIOS) transfers control to the MBR during startup.

Computer System

An electronic device comprised of hardware, software, and data that accepts input, processes it, and provides output.

Operating System (OS)

System software loaded first upon power-on that enables communication between a user and the computer, manages hardware/software resources, and provides services for programs.

Hardware

The physical components of a computer system and its peripherals (e.g., CPU, memory, monitor, keyboard).

Software

The set of computer programs that enable hardware to perform tasks. Includes both application software and system software.

Data

Information accepted as input, processed, and given as output by a computer system.

CPU (Central Processing Unit)

The primary component of a computer responsible for executing instructions. Consists of the ALU, Control Unit, and Registers.

ALU (Arithmetic-Logic Unit)

The part of the CPU that performs arithmetic (+, -, *, /) and logical (AND, OR, NOT) operations

Control Unit

The part of the CPU that directs the operations of the processor, instructing other components on what to do

CPU Register

A small, high-speed storage area within the CPU used to hold data, instructions, or addresses temporarily.

Word

The number of bits a CPU is able to deal with at a time (e.g., 32 bits for an x86 CPU, 64 bits for an x64 CPU).

Core

A physical CPU on a single processor unit. Multi-core processors have multiple cores.

Thread

Viewed by the OS as a logical CPU; allows for concurrent execution of processes.

Bus

An electrical pathway (circuit) that connects different parts of the motherboard to allow data and control signals to travel between components

Data Bus

A bidirectional bus that carries data between the CPU and other components.

Address Bus

A unidirectional bus that carries information about the location of data in memory or I/O devices.

Control Bus

A unidirectional bus that carries control signals from the Control Unit for synchronization and operation management.

Bus Speed

The rate at which data can be transferred on a bus.

Clock Speed (Clock Rate, CPU Frequency)

The number of cycles a CPU can execute per second, measured in Hertz (Hz).

CPU Speed

The number of calculations or instructions a CPU can process per second, influenced by clock speed, cores, and cache.

CPU Cache

A small, fast memory located near the CPU that stores copies of frequently used data and instructions to reduce access time to main memory.

MBR (Master Boot Record)

Information in the first sector of a hard disk that contains the boot loader and defines the primary and extended partitions. Limited to 2TB maximum partition size and 4 primary partitions.

GPT (GUID Partition Table)

A newer partitioning scheme that supports larger disk sizes (up to 8 ZB) and more partitions (up to 128 in Windows). Requires UEFI and 64-bit systems.

Bootloader (Bootstrap Code)

A small program stored in the MBR or elsewhere that loads the operating system into memory.

BIOS (Basic Input/Output System)

Firmware that performs initial hardware tests during startup before transferring control to the bootloader.

UEFI (Unified Extensible Firmware Interface

A newer firmware interface that replaces BIOS, required for using GPT on many systems

Main Memory (Primary Memory, RAM)

Electronic holding place for data and instructions a computer needs to access quickly for immediate use.

RAM (Random Access Memory)

Integrated circuits that make up the main memory. Volatile storage.

Secondary Memory (Secondary Storage)

Non-volatile storage devices used for long-term data storage (e.g., Hard Disk Drive, Solid State Drive).

Virtual Memory

A memory management technique that uses both RAM and secondary storage to provide a larger virtual address space than the available physical memory.

Paging

A virtual memory technique that divides primary memory (page frames) and processes (pages) into fixed-size blocks for efficient loading and swapping between RAM and disk.

Page Table

Where the OS stores the mapping between virtual addresses and physical addresses in memory.

Paged In (Swap In)

The process of transferring a page from disk to RAM.

Paged Out (Swap Out)

The process of transferring a page from RAM to disk.

Demand Paging

A virtual memory strategy where pages are loaded into physical memory only when they are needed or demanded during program execution.

Pagefile.sys

A system file in Windows used as part of the virtual memory system to swap data between RAM and disk.

Process States

Different stages a process can be in during its lifecycle (Created/New, Ready/Waiting, Running, Terminated, Blocked, Swapped out and waiting, Swapped out and blocked).

Device Driver

Software that acts as an interpreter between the operating system and a specific hardware device, translating commands.

API (Application Programming Interface)

A set of protocols, routines, and tools for building software applications. Used by application programmers to issue instructions to the OS and device drivers.

Kernel

The core of the operating system that manages system resources and facilitates communication between hardware and software.

Specification

A set of documented requirements to be met by a material, design, product, or service, including hardware and software requirements.

Software Requirement

Defines the software resources and prerequisites needed for an application to run.

Hardware Requirement

Defines the specifications of hardware compatible with required software.

File System

Controls how data is stored and retrieved on a storage device, provides access control, and stores metadata.

FAT32 (32-bit File Allocation Table)

A file system commonly used for removable media, with a maximum file size limit of 4GB.

NTFS (New Technology File System)

A file system used by Windows with larger maximum file and volume sizes and more features than FAT32.

EXT4 (Fourth Extended Filesystem)

A common default file system for Linux distributions like Ubuntu.

XFS

A common file system for Linux distributions like Red Hat and SuSe.

APFS (Apple File System)

The default file system for macOS and iOS devices.

Disk Partition

Dividing a storage device into multiple logical storage units.

System Partition

The partition allocated for the operating system files.

Data Partition

The partition allocated for storing user data.

Multi-boot

The ability to install and select between multiple operating systems on a single computer