Scheduling
- 1. Scheduling Bag of Tasks on Dedicated Systems • Min-Min • Max-Min • Sufferage
- 2. Min-Min Heuristic • For each task determine its minimum completion time over all machines • Over all tasks find the minimum completion time • Assign the task to the machine that gives this completion time • Iterate till all the tasks are scheduled
- 3. Example of Min-Min T1 T2 T3 M1 140 20 60 M2 100 100 70 Stage 1: Stage 2: Stage 3: T1-M2 = 100 T1-M2 = 100 T1-M1 = 160 T2-M1 = 20 T3-M2 = 70 T3-M1 = 60 Assign T2 to M1 Assign T3 to M2 Assign T1 to M1 T1 T3 M1 160 80 M2 100 70 T1 M1 160 M2 170 T2 T3 T1 M1 M2 20 70 160
- 4. Max-Min Heuristic • For each task determine its minimum completion time over all machines • Over all tasks find the maximum completion time • Assign the task to the machine that gives this completion time • Iterate till all the tasks are scheduled
- 5. Example of Max-Min T1 T2 T3 M1 140 20 60 M2 100 100 70 Stage 1: Stage 2: Stage 3: T1-M2 = 100 T2-M1 = 20 T2-M1 = 80 T2-M1 = 20 T3-M1 = 60 T3-M1 = 60 Assign T1 to M2 Assign T3 to M1 Assign T2 to M1 T2 T3 M1 20 60 M2 200 170 T2 M1 80 M2 200 T3 T1 T2 M1 M2 60 100 80
- 6. Sufferage Heuristic • For each task determine the difference between its minimum and second minimum completion time over all machines (sufferage) • Over all tasks find the maximum sufferage • Assign the task to the machine that gives this sufferage • Iterate till all the tasks are scheduled
- 7. Example of Sufferage T1 T2 T3 M1 140 20 60 M2 100 100 70 Stage 1: Stage 2: Stage 3: T1 = 40 T1 = 60 T3 = 90 T2 = 80 T3 = 10 T3 = 10 Assign T2 to M1 Assign T1 to M2 Assign T3 to M1 T1 T3 M1 160 80 M2 100 70 T3 M1 80 M2 170 T2 T1 T3 M1 M2 20 100 80