Examples
Examples
Try the starting example
- Jobs: name, arrival seconds, duration seconds
- A,0,5 B,0,3 C,1,2 D,4,1
- Identical workers
- 2
- Last completion time (seconds)
- 6
- Job worker, start and completion
- A: W1 0–5; B: W2 0–3; C: W2 3–5; D: W1 5–6
- Mean waiting time (seconds)
- 0.75
- Worker utilisation over 0 to last completion (%)
- 91.666667
- Jobs that waited
- 2
Try another scenario
- Jobs: name, arrival seconds, duration seconds
- A,0,5 B,0,3 C,1,2 D,4,1
- Identical workers
- 1
- Last completion time (seconds)
- 11
- Job worker, start and completion
- A: W1 0–5; B: W1 5–8; C: W1 8–10; D: W1 10–11
- Mean waiting time (seconds)
- 4.5
- Worker utilisation over 0 to last completion (%)
- 100
- Jobs that waited
- 3
Calculation method
Calculation method
Last completion time (seconds)
FCFS by arrival then input order; assign each job to the worker with the earliest availability, breaking worker ties by index.
Job worker, start and completion
Start=max(arrival, worker free time); completion=start+duration.
Mean waiting time (seconds)
Mean(start−arrival).
Worker utilisation over 0 to last completion (%)
Total job duration / (workers × final completion) × 100. Includes idle time from t=0.
Jobs that waited
Count jobs whose start is strictly after arrival.
Symbols and units
- a
- Jobs: name, arrival seconds, duration seconds
- b
- Identical workers
Use the units shown. A list keeps the order in which you enter its values. The symbol ^ means “raised to the power of”.
Assumptions & limits
Assumptions & limits
- Finite nonpreemptive independent jobs, identical workers, no priorities, failures or future generated arrivals. FCFS is the declared rule, not an optimum-makespan claim.
Are these inputs private?
These calculations run in your browser. A shared link contains the values you choose to share. Only questions submitted to the separate AI finder are sent to OpenAI.
Further reading
OpenStax: arithmetic and geometry ↗
Background reading; this does not imply endorsement or independent review of SumFizz.