CPU Scheduling Algorithms (2)

CPU Scheduling Algorithms

1. preemptive scheduling algorithms
2. non-preemptive scheduling algorithms

• CPU scheduling algorithms are applied only to processes which are in the ready state.
• Processes which are in I/O state will be blocked and so those processes will not be considered by schedulling algorithms while scheduling

 

Shortest Job First Scheduling Algorithms

 

process Id	Arrival time	burst time
1	2	3
2	3	2
3	4	3
4	6	1
5	8	2

 

 

process Id	complete time	TAT	WT
1	5	3	0
2	7	4	2
3	13	9	6
4	8	2	1
5	10	2	0

 

schedule length = completion time of last process - AT of first process

13 - 2 = 11

 

throughput = Number of process / schedule length