You will be implementing following CPU scheduling algorithms using C or C++ with the assumption that all jobs are CPU bound i.e. they do not block for I/O:

• First Come First Serve (FCFS)  [Non-preemptive]           3 points
• Shortest Job First (SJF)  [Preemptive]                          4 points
• Priority Scheduling [Preemptive]                                  3 points

 

You will profile the performance of these algorithms by tracking several measures of effectiveness such as average turnaround time, average waiting time, and throughput. The turnaround time for a process is the difference between a job’s submission and completion times. The average turnaround time reports the average turnaround time for the set of processes that were scheduled. The waiting time for a process reflects the total amount of time spent by that process in the ready queue. The average waiting time reports the average waiting time for the set of processes that were scheduled. The throughput for a scheduling algorithm measures the total number of tasks processes that completed per unit of time. 

 

1. Requirements of Task 

 

1. You need to read the list of processes for your scheduling algorithms from a file. Every line in this file includes a record with comma separated fields.  The format for this record is the following: ,, , .  Not all fields are used by all scheduling algorithms. For example, for FCFS you only need the process IDs, arrival times, and burst durations.  All processes in your input files will be provided a unique process ID.  The arrival times and burst durations are integers. Process priorities have a range of [1-50]; the lower this number, the higher the priority i.e. a process with priority=1 has a higher priority than a process with priority=2.

2. Implement FCFS (non-preemptive) and report average turnaround time, average waiting time, and throughput. 

3. Implement SJF (preemptive) and report average turnaround time, average waiting time, and throughput. 

4. Implement priority scheduling (preemptive) and report average turnaround time, average waiting time, and throughput. 

 

1. Command line arguments for grading:

> ./Scheduler

The input_filename contains information about the processes that need to be scheduled. 

 

example outputs

Here's an easy sample input :

1,0,3,5
2,2,4,2
3,3,1,3
4,8,3,4
5,10,4,1

You should be getting this output:

--- FCFS ---
Average Turnaround Time: 4.200
Average Waiting Time: 1.200
Throughput: 0.333

--- SJFP ---
Average Turnaround Time: 3.600
Average Waiting Time: 0.600
Throughput: 0.333

--- Priority ---
Average Turnaround Time: 5.400
Average Waiting Time: 2.400
Throughput: 0.333