Chapter 3: Operating Systems History and Examples

FIRST GENERATION

SERIAL PROCESSING

SERIAL PROCESSING

FIRST GENERATION

MAINFRAME COMPUTERS

• 1st Generation

• Used in the late 1940s and early 1950s

• Massive, expensive, slow, and very primitive

FIRST GENERATION

No operating systems, only “bare” machines

FIRST GENERATION

Can only be used by one person at a time, and is processed one after another

FIRST GENERATION

Entered by toggle switches by turning it on or off

FIRST GENERATION

Used punched cards, with square holes representing binary characters or numbers

Punched Cards, Square Holes

The First Generation used ________ with __________ representing binary characters or numbers.

FIRST GENERATION

Had a keypunch to puncture holes in the punched cards

FIRST GENERATION

Had a punch card reader to read the cards, generate the electric form of the program, and load it in the main memory for the compilation

FIRST GENERATION

No fixed disks or hard disks

KEYPUNCH

It is a FIRST GENERATION TOOL used to PUNCTURE HOLES in the punched cards.

Punch Card Reader

It is a FIRST GENERATION TOOL used to read the cards, generate the electric form of the program, and load it in the main memory for the compilation

THIRD GENERATION

MULTI-PROGRAMMED SYSTEMS

MULTI-PROGRAMMED SYSTEMS

It consists of THREE PROGRAMS

Program 1 (I/O Operation)

Program 1 performs I/O Operation

CPU (Program 2 Execution)

The CPU starts executing Program 2

Program 2 (I/O Operation)

Program 2 performs I/O Operation

CPU (Program 3 Execution)

The CPU starts executing Program 3

Program 3 (I/O Operation)

Program 3 performs I/O Operation

THIRD GENERATION

Several programs will be present in the main memory.

THIRD GENERATION

Job scheduling should be performed wherein the Operating System selects which among the programs will be loaded into the main memory

Job scheduling

should be performed wherein the Operating System selects which among the programs will be loaded into the main memory.

FOURTH GENERATION

TIME-SHARING SYSTEMS

FOURTH GENERATION

The CPU is assigned to a user or process for a time period, also called a time slice or a time quantum, by the operating system.

Time Slice, Time Quantum

In the fourth generation, the CPU is assigned to a user or process for a time period, also called a _____________, by the operating system.

FOURTH GENERATION

After a user consumes its time slice, the CPU is assigned to another user or process and so on.

MULTIPROGRAMMING

The CPU will continue to execute a program until an I/O Operation is encountered

MULTI-TASKING

The CPU will continue to execute a program until the time quantum has ended.

PERSONAL COMPUTER SYSTEMS

• It was assumed that only the user process would run at any given time since the PC is used by the programmer only.

PERSONAL COMPUTER SYSTEMS

The microprocessors at this time did not have the necessary hardware support to provide the protection to processes

MULTIPROCESSOR SYSTEMS

It refers to the SYMMETRIC MULTIPROCESSING (SMP) and ASSYMETRIC MULTIPROCESSOR (AMP)

Symmetric Multiprocessing (SMP)

Only one operating system is used, and each processor runs the same operating system.

Symmetric Multiprocessing (SMP)

Load balancing is used to distribute the load evenly over the processors.

Assymetric Multiprocessor (AMP)

Also called Distributed Memory Multiprocessors.

Assymetric Multiprocessor (AMP)

Each processor has its own memory. In this system, specific tasks are assigned to each processor

NETWORK OPERATING SYSTEMS

Allow the sharing of resources and actual communication among computers connected in a network

NETWORK OPERATING SYSTEMS

The entire network of computers is perceived by a user as one big and powerful computing machine.

REAL-TIME SYSTEMS

Produce correct results on a very strict time constraint, which is usually very small.

REAL-TIME SYSTEMS

Examples of this are medical monitoring systems, machine control systems, guided missile systems, and airplane control systems

HANDHELD SYSTEMS

Have slower processors and smaller memory compared to PCs

HANDHELD SYSTEMS

Examples of handheld systems are Personal Digital Assistants (PDAs), Smart Devices such as Tablet and Mobile Phones