1. Rate Monotonic Scheduling :
Rate monotonic scheduling is a priority algorithm in which the priorities are assigned to the processes according to the cycle time, a process with the least task duration is given the priority. It is preemptive: the highest priority process will preempt the other processes. The priority of a process is inversely proportional to its cycle time.
2. Deadline Monotonic Scheduling :
Deadline monotonic scheduling is a priority algorithm in which the priorities are assigned to the processes based on their respective deadlines. A deadline is a time limit in which a task has to be completed. The process with the shortest deadline is assigned the highest priority. It is also preemptive. The priority of a process is inversely proportional to the deadline.
Difference between Rate Monotonic Scheduling and Deadline monotonic Scheduling :
|Rate Monotonic Scheduling||Deadline Monotonic Scheduling|
|In Rate monotonic Scheduling, priorities are assigned to tasks according to the shortest cycle time||In Deadline monotonic Scheduling, priorities are assigned to tasks according to the shortest deadline.|
|Implementation of Rate monotonic scheduler is simple and can be executed using FIFO (First-in First-out) scheduling.||Implementation of Deadline monotonic scheduler is complicated and is time-taking process.|
|The choice of priority is decided based on the computation time or active frequency.||The choice of priority is decided based on which task is ready to be executed first.|
|Priority is inversely proportional to the cycle time.||Priority is inversely proportional to the deadline (time limit).|
|RMA is not optimal with periodic tasks when deadline and period differ.||DMA is more proficient than RMA when deadline and period differ.|