Here is a comparison between the Shortest Job First (SJF) and Shortest Remaining Job First (SRJF) scheduling algorithms in CPU Scheduling in operating systems :
| Feature | Shortest Job First (SJF) | Shortest Remaining Job First (SRJF) |
|---|---|---|
| Responsiveness | Lower waiting time for processes, leading to high responsiveness | Lower waiting time for processes, leading to high responsiveness |
| Memory requirements | Requires additional memory for scheduling information | Requires additional memory for scheduling information |
| Task completion | Results in shorter completion time for tasks | Results in shorter completion time for tasks |
| Performance prediction | Easy to predict performance | Easy to predict performance |
| Overhead | Higher overhead compared to FCFS | Higher overhead compared to FCFS |
| Load balancing | Results in balanced distribution of load | Results in balanced distribution of load |
| Real-time applications | Suitable for real-time applications | Suitable for real-time applications |
| Batch processing | Suitable for batch processing | Suitable for batch processing |
| Multitasking | Suitable for multitasking | Suitable for multitasking |
| Scheduling decisions | Based on burst time | Based on remaining burst time |
| Process state | Process state information is required | Process state information is required |
| Predictability | Good predictability | Good predictability |
| Starvation | Prevents starvation of long processes | Prevents starvation of long processes |
| CPU utilization | Higher average CPU utilization | Higher average CPU utilization |
| Process preemption | Does not allow process preemption | Allows process preemption |
In conclusion, both SJF and SRJF are scheduling algorithms used in CPU Scheduling in operating systems. SJF executes the process with the shortest burst time first, while SRJF executes the process with the shortest remaining burst time first. Both algorithms have similar features in terms of responsiveness, memory requirements, task completion, performance prediction, load balancing and suitability for real-time and batch processing applications. However, SRJF allows process preemption, while SJF does not. The choice of scheduling algorithm depends on the specific requirements and constraints of the system and the workload being scheduled.
