Don’t Do It: Ignore Worst-Case Execution Time (Download)
In real-time embedded systems, even a single missed deadline can compromise safety and reliability. From automotive and avionics to industrial automation and defense, developers must demonstrate that worst-case execution time (WCET) is well understood and consistently bounded, ensuring a reliable upper limit that no task will ever exceed during operation.
Estimating WCET is far from straightforward, especially in modern multicore systems, so it isn’t surprising that even the most seasoned development teams underestimate it and often implement it poorly. The worst-case execution time for mission-critical tasks can fluctuate depending on what else is running, which resources are shared, and how the processor behaves under load.