How can you test software running on a continuous loop expecting external inputs?

This is not inherently a multicore problem – it can also be encountered on single core systems. The additional complexity of high-performance multicore platforms may add to the required effort to construct the test vectors and test environment required for software characterization, which must be sufficient to construct “worst-case” scenarios. This may require external stimulation or inputs that can add to the complexity of the activity as it may make it hard to synchronize events or create other challenges. This is often achievable, but the additional effort and de-risking activities should be considered during planning.