Difference between Firm Real-time Tasks and Soft Real-time Tasks
Real-time tasks are generally classified as – Hard and Soft but on a wide range, Real-time tasks are classified as:
- Hard Real-time Tasks
- Firm Real-time Tasks
- Soft Real-time Tasks
1. Firm Real-time Tasks : Firm real-time tasks are such type of real-time tasks which are associated with time bound and the task need to produce the result within the deadline. Although firm real-time task is different from hard real-time task as in hard real-time once deadline is crossed and task is not completed, system fails but in case of firm real-time task even after the passing of deadline, system does not fail. Example:
1. Video conferencing 2. Satellite based tracking
2. Soft Real-time Tasks : Soft real-time tasks are such type of real-time tasks which are also associated with time bound but here timing constraints are not expressed as absolute values. In soft real-time tasks, even after the deadline result is not considered incorrect and system failure does not occur. Example:
1. Web browsing 2. Railway Ticket Reservation
Difference between Firm and Soft Real-time Tasks :
FIRM REAL-TIME TASKS | SOFT REAL-TIME TASKS |
---|---|
It needs to be completed within the deadline. | It also needs to be completed within deadline but not strictly. |
The value of associated timing constraint is taken as absolute. | The value of associated timing constraint is taken as average value. |
The utility of result becomes zero after the deadline. | The utility of result decreases after the deadline but it gradually becomes zero. |
Result obtained after deadline is considered incorrect. | Result obtained after deadline is not incorrect. |
It is widely used in multimedia applications. | It is less used in such applications. |
It is less used in practical applications. | It is widely used in practical applications. |
Example: Satellite based tracking. | Example: Railway ticket reservation. |
Consequences are severe but not catastrophic (e.g., financial loss or safety risk). | Consequences are less severe (e.g., degraded performance or reduced quality). |
Focused on processing critical tasks with high priority. | Focused on processing tasks with lower priority. |
Highly predictable, with well-defined and deterministic behavior. | Less predictable, with behavior that may vary depending on system load or conditions. |
Dedicated and exclusive resources to ensure timely processing. | Shared resources, which may result in resource contention and delays. |