Hard real-time systems have strict, non-negotiable timing constraints where tasks must complete within a guaranteed timeframe.
[ ] Use real-time operating systems (RTOS) to ensure deterministic scheduling and response times.
[ ] Prioritize critical tasks and allocate fixed time slots for their execution.
Soft real-time systems have timing constraints that are important but not as strict as hard real-time systems. Missing a deadline is undesirable but not catastrophic.
[ ] Implement priority scheduling to ensure critical tasks are given preference.
[ ] Set priorities based on the criticality of the task.
Task Scheduling: Use appropriate task scheduling algorithms to ensure timely execution.
[ ] Employ priority-based scheduling algorithms to give precedence to high-priority tasks.
[ ] Consider rate monotonic scheduling for periodic tasks.
Real-Time Clocks and Timers:
[ ] Utilize hardware-based real-time clocks for accurate timekeeping.
[ ] Set timers to trigger periodic or one-shot tasks at precise intervals.
Deadline Monitoring:
[ ] Monitor task execution to ensure that deadlines are not missed.
[ ] Implement mechanisms to handle tasks that exceed their allotted time.
Deterministic Execution Paths: Minimize variations in execution times to achieve deterministic behavior.
[ ] Profile and optimize code to reduce execution time variability.
[ ] Minimize the use of non-deterministic constructs in the code.
Real-Time Guarantees: Provide guarantees for response times and completion times.
[ ] Analyze worst-case execution times (WCET) to determine task execution bounds.
[ ] Use scheduling and resource allocation techniques to meet guarantees.
Input and Output Constraints: Minimize the latency associated with input and output operations.
[ ] Use asynchronous I/O operations to overlap computation and communication.
[ ] Optimize data serialization and deserialization for efficient communication.
Task Offloading: Offload non-critical tasks to secondary processors or devices.
[ ] Identify tasks that can be offloaded without affecting critical functions.
[ ] Distribute computational load to improve overall system performance.
Interrupt Handling:
[ ] Prioritize interrupts based on criticality.
[ ] Minimize interrupt service routine (ISR) execution time.
Resource Reservation: Reserve resources such as CPU time, memory, and bandwidth for critical tasks.
[ ] Use resource reservation mechanisms to guarantee availability for critical tasks.
[ ] Monitor and enforce resource usage limits.
Real-Time Networking: Minimize communication latency in real-time networks.
[ ] Use Real-Time Publish-Subscribe (RTPS) middleware for efficient and low-latency communication.
[ ] Optimize network configurations for minimal jitter and latency.
Testing and Validation:
[ ] Use stress testing and worst-case scenario testing to ensure the system meets real-time constraints.
[ ] Simulate different operating conditions to verify performance under varying workloads.
Continuous Monitoring:
[ ] Use real-time monitoring tools to track task execution times, resource usage, and system health.
[ ] Implement alarms or notifications for deviations from expected performance.
Hard real-time systems have strict, non-negotiable timing constraints where tasks must complete within a guaranteed timeframe.
Soft real-time systems have timing constraints that are important but not as strict as hard real-time systems. Missing a deadline is undesirable but not catastrophic.
Task Scheduling: Use appropriate task scheduling algorithms to ensure timely execution.
Real-Time Clocks and Timers:
Deadline Monitoring:
Deterministic Execution Paths: Minimize variations in execution times to achieve deterministic behavior.
Real-Time Guarantees: Provide guarantees for response times and completion times.
Input and Output Constraints: Minimize the latency associated with input and output operations.
Task Offloading: Offload non-critical tasks to secondary processors or devices.
Interrupt Handling:
Resource Reservation: Reserve resources such as CPU time, memory, and bandwidth for critical tasks.
Real-Time Networking: Minimize communication latency in real-time networks.
Testing and Validation:
Continuous Monitoring: