Chapter 1 (Tanenbaum 4th edition)

Operating System

provides user with a better, simpler, cleaner, model of the computer, and is a resource manager

Shell

text based program programs used by users to interact with operating system

GUI(Graphic User Interface)

uses icons to get work done on the operating system

Kernel Mode

(also called supervisor mode). This mode has complete access to all of the hardware and can execute any instruction the machine is capable of executing.

User Mode

this mode only has a subset of the machine instructions available

Multiplexing

sharing resources in two different ways; in time and space

The First Generation Keys(1945-55)
Vacuum Tubes

a) Vacuum tubes main hardware / break-thru Plug boards and Punch Cards.

b) all programs in absolute machine language
c) group of people to operate

The Second Generation Keys(1955-65)
Transistors & Batch System

a) Transistors main hardware/ Batch system and Mainframes Major Break thru

b) separation of duties

The Third Generation(1965-1980)
IC & Multiprogramming

a) Integrated Circuits main hardware/ 3 main breakthroughs
1) multiprogramming
2) spooling
3) time sharing

The Fourth Generation(1980-present)
Personal Computers

Large Scale Integration(LSI) main hardware
2 major breakthroughs
1) GUI - user friendly
2) Network Operating System

The Fifth Generation(1990-present)
Mobile Computers

combined phone and PDA(personal digital assistance)

Input/Output Devices (I/O)

consists of two parts
- Controller(the driver)
- The device itself
-must have drivers to work

Mainframes

computers that took up an entire room with staffs of professional operators to run them.

batch system

a type of system development for the earliest computers that used punched cards or tape for input, which were entered in a "batch"

Integrated Circuits

Chips that contain large numbers of transistors integrated into silicon, produced data faster and was smaller and faster that its predecessor, 3rd generation

multiprogramming

The technique of keeping multiple programs in main memory at the same time, competing for the CPU

spooling

The process of placing items in a buffer so they can be retrieved by the appropriate device (such as a printer) when needed.

Time Sharing

users may share the computer system resources at the same time; each user acts independently

Caching system questions

1. when to put a new item into cache
2. which cache line to put the new item in
3. which item to remove from the cache when a slot is needed
4. Where to put a newly evicted item in the larger memory

Cache memory

memory used for frequently used programs

RAM memory

random access memory; main memory , loses content when switched off

ROM memory

ROM is memory containing hardwired instructions that the computer uses when it boots up, before the system software loads.

Solid State Disks

having no moving parts and stores data in flash memory

Virtual memory

Hard Drive space acting as memory, 1.5 X Ram

Memory Management Unit

maps virtual address space to physical address space

Device Driver

A software program that provides the instructions your computer needs to communicate with a device.

Busy Waiting

software loop that checks the I/O status waiting for the done state

interrupt

occurs when a controller detects an end of the transfer.

Direct Memory Access

an I/O technique that allows a control unit to access main memory directly and transfer data without the intervention of the CPU

PCIe

the main bus used to connect peripheral devices.

Direct Media Interface

This connects Northbridge and to Southbridge.

USB

Universal serial bus port - allows you to connect different pieces of equipment to the computer

SCSI

used to connect fast disk, scanners and other devices needing considerable bandwidth

Plug and Play

system automatically collects information about the I/O devices

Mainframe Operating Systems (1)

Room size computers
offers 3 kinds of server
-batch system-process without user interrupt
-transaction process - handles large numbers
-time sharing - allows multiple remote users

--specialized operating system used to run Mainframe

Server Operating Systems (2)

-Solaris, FreeBSD, Linux, Windows Server 201X
-Can provide print server, file service, or web service

Multiprocessor Operating System (3)

systems called parallel computers, multi-computers, or multiprocessors.

need special operating systems

Personal computer Operating Systems(4)

modern ones all support multiprogramming, often with dozens of programs started up at boot time.

job to provide good support to a single user

Handheld Computer Computer Operating System(5)

originally known as PDA

Embedded Operating System(6)

-runs on computers that control devices that are not generally thought of as a computer.

-microwaves -mp3 players
-TV sets -cars
-DVD recorders
-traditional phone

Sensor - Mode Operating System(7)

measures - precipitation - detect movement
- temperature - measure waves
- enemy movement

designed to do one task, most of the time wireless

Real Time Operating System(8)

- Time is key Parameter
- Hard Real time must occur at a certain time
- Soft Real time can miss an occasional deadline

Smart Card Operating System

-limited - Java Oreiented
-small

Process

a program in execution

Directory

a way to group files together
-every file can be specified by giving Path Name
from the top of the directory using Root Name

Special File

two types

- block files - used to model devices that consist of a collection of randomly addressable blocks such as disks

- character special files are used to model printers, modems, and other devices that accept or output a character stream.

Monolithic Systems(1)

-the big mess
-everything in kernel mode

Layered Systems(2)

Operating system organized in layers each one constructed upon the one below it

Microkernels(3)

basic design is to achieve high reliability by splitting the operating system into small well defined modules

Virtual Machines

Virtual machines can run any Operating System that will run directly on the bare system.

Exokernels

allows the use up to 4 Operating Systems