First there was batch

1
First there was batch

• Serial processing
• Waiting jobs sit on a job queue until they can be
  processed
• Things processed in first-in first-out order
  (FIFO)

2
Batch processing
Things done, output results
Jobs .. Data, things to do
Machine Domain
Job Queue
Job execution
3
An IBM punch card
To read a card one character at a time
4
Programs used punched cards
5
We create codes using presence or absence hole
punched
I
0
0
0
0
1
1
0
1
1
Presence
0
Absence
This concept has carried through to modern
computing codes used to identify characters and
letters.
6
Interactive processing
Machine Domain
Job execution
7
Software classification
8
User
User
Shell
Kernel
User
User
9
Starting the system up

• Bootstrap BIOS (Basic Input Output system)
• Permanently written instructions that load the
  operating system software into the computer
  memory

10
A process
Set of instructions

• Current state
• At what point in instruction set
• State of data being processes

Data (new, modified)
11
Time sharing
Proc B
Proc B
swap
swap
swap
Proc A
Proc A
Time