Day 02Part 03- Various types of times in Process Scheduling algorithm, Arrival, Burst TAT.
Day 02Part 03- Various types of times in Process Scheduling algorithm, Arrival, Burst TAT.
Contents [hide]
- 1 Day 02 | Part 03 – Process Scheduling Algorithm: Various Types of Times
- 2 Arrival Time (AT)
- 3 Burst Time (BT)
- 4 Turnaround Time (TAT)
- 5 Waiting Time (WT)
- 6 Completion Time (CT)
- 7 Response Time (RT)
- 8 Summary Table:
- 9 Example Problem:
- 10 Day 02Part 03- Various types of times in Process Scheduling algorithm, Arrival, Burst TAT.
- 11 Operating System : Scheduling Algorithm – Jaunpur
- 12 PROCESSES AND CPU Scheduling
Day 02 | Part 03 – Process Scheduling Algorithm: Various Types of Times
Process scheduling in an operating system involves different types of times that determine the efficiency and execution sequence of processes. Let’s explore them one by one:
Arrival Time (AT)
Definition: The time when a process enters the ready queue.
Example: If Process P1 arrives at time 0 ms and P2 at 2 ms, then:
- AT(P1) = 0 ms
- AT(P2) = 2 ms
Burst Time (BT)
Definition: The total time required by a process to execute on the CPU.
Also called Execution Time or CPU Time.
Example:
- P1 requires 5 ms to complete execution.
- P2 requires 8 ms to complete execution.
- So, BT(P1) = 5 ms, BT(P2) = 8 ms.
Turnaround Time (TAT)
Definition: The total time taken by a process from arrival to completion.
Formula:
TAT=CompletionTime(CT)−ArrivalTime(AT)TAT = Completion Time (CT) – Arrival Time (AT)
Example: If a process arrives at 0 ms and completes at 10 ms, then:
- AT = 10 – 0 = 10 ms
Waiting Time (WT)
Definition: The total time a process spends waiting in the ready queue before execution.
Formula:
WT=TurnaroundTime(TAT)−BurstTime(BT)WT = Turnaround Time (TAT) – Burst Time (BT)
Example:
- If TAT = 10 ms, BT = 5 ms, then
- WT = 10 – 5 = 5 ms
Completion Time (CT)
Definition: The time at which a process finishes execution.
Example: If process P1 finishes execution at 12 ms, then
- CT(P1) = 12 ms
Response Time (RT)
Definition: The time from arrival to the first execution of a process.
Formula:
RT=FirstExecutionTime−ArrivalTime(AT)RT = First Execution Time – Arrival Time (AT)
Example:
- If a process arrives at 0 ms but starts execution at 3 ms, then
- RT = 3 – 0 = 3 ms
Summary Table:
| Time Type | Definition | Formula |
|---|---|---|
| Arrival Time (AT) | When process arrives in the queue | Given in question |
| Burst Time (BT) | Total execution time | Given in question |
| Turnaround Time (TAT) | Time from arrival to completion | CT - AT |
| Waiting Time (WT) | Time spent waiting in queue | TAT - BT |
| Completion Time (CT) | When process finishes execution | Given or calculated |
| Response Time (RT) | Time from arrival to first execution | First Execution - AT |
Example Problem:
Given Processes:
| Process | AT | BT |
|---|---|---|
| P1 | 0 | 5 |
| P2 | 1 | 3 |
| P3 | 2 | 8 |
If scheduled using FCFS (First Come First Serve), find TAT, WT, and RT.
Would you like me to solve this example step by step?