OS Overview

Operating System

• a program that abstracts and manages hardware resources for user programs

Hardware Resources

• CPU
  • processor: executes instructions
  • single core CPU
  
  • multicore CPU
  
  • CPU chip
  
  • how do we directly interact with CPU?
  • instruction stream
  • address of next instruction resides in %rip, hw automatically increments it to continue execution
  • who sets up the first %rip value for a process?
• DRAM
• main memory, volatile, byte-addressable

• a process must be brought into memory in order to execute, why?
• Input/Output
• storage (persistent) devices
• persistent, block-addressable
• hard drive (spinning disks)

• solid state drive (SSD)

• flash drives
• Network Adapter (NIC)
• Input devices: mouse, keyboard, webcam, microphone
• Output devices: monitor, headphones, speakers

OS Roles

• How does OS abstract these hardware resources?
• CPU => ?
• Memory => ?
• Storage => ?
• Network adapter => ?
• Keyboard => ?
• Why does the OS provide these abstractions?
• How does the OS provide these abstractions?