- Identify root function
- Select WCET tab
- Lookup data for root function
- Worst-case execution time value
We use the W-OverET value (see column heading). In this case “W” means worst-case, “over” means overall (i.e. including execution time of the root function and its child functions), “ET” means execution time. As you can see from this report many additional time values are also available. Worst-case execution time reported by tools is often subject to “pessimism” (i.e. reporting that the WCET is greater than is actually the case). In DO-178B we describe three ways in which pessimism can be reduced.