Sheduling analysis real-time systems

The term scheduling analysis in real-time computing includes the analysis and testing of the scheduler system and the algorithms used in real-time applications. In computer science, real-time scheduling Analysis is the evaluation, testing and verification of the scheduling system and the algorithms used in real-time operations. For critical operations, a real-time system must be tested and verified for performance. In computer science, testing and verification is also known as model checking.

A real-time scheduling System is composed of the scheduler, clock and the processing hardware elements. In a real-time system, a process or task has schedulability; tasks are accepted by a real-time system and completed as specified by the task deadline depending on the characteristic of the scheduling algorithm. Modeling and evaluation of a real-time scheduling system concern is on the analysis of the algorithm capability to meet a process deadline. A deadline is defined as the time required for a task to be processed.

For example, in a real-time scheduling algorithm a deadline could be set to five nano-seconds. In a critical operation the task must be processed in the time specified by the deadline (i.e. five nano-seconds). A task in a real-time system must be completed “neither too early nor too late;..”. A system is said to be unschedulable when tasks can not meet the specified deadlines. A task can be classified as either a periodic or aperiodic process.

The criteria of a real-time can be classified as hard, firm or soft. The scheduler set the algorithms for executing tasks according to a specified order. There are multiple mathematical models to represent a scheduling System, most implementations of real-time scheduling algorithm are modeled for the implementation of uniprocessors or multiprocessors configurations. The more challenging scheduling algorithm is found in multiprocessors, it is not always feasible to implement a uniprocessor scheduling algorithm in a multiprocessor. The algorithms used in scheduling analysis “can be classified as pre-emptive or non-pre-emptive".

...
Wikipedia