Time-Sharing.ppt divide CPU equally among the users

multiple terminals into one machine
each user has illusion of entire machine to him/herself
Optimized response time

1. Time Sharing /
Multi-Tasking

2. Timesharing
•multiple terminals into one machine
•each user has illusion of entire
machine to him/herself
•Optimized response time
Supports interactive use :
•divide CPU equally among the users
•CPU can move among programs and
users if user jobs are interactive
Timeslicing
E.g. MIT CTSS

3. Terminals are connected
to the main computer and
used for input and output.
No processing is made.
They do not have CPUs.
Main computer; having a CPU
executing processes by
utilization of the OS, (e.g. UNIX).

4. Time Sharing –time quantum
P2
P3
P1
I/O
CPU
OS
0
max

5. Time Sharing
P2
P3
P1
I/O
CPU
OS
0 0
Clock
1234
max