[peerst]

Soft is the new hard ;-) If you reason about hard realtime you pretty soon end up with the question: how high can the probability be that it misses a deadline. If you run on modern embedded CPU's with pipelines and caches its often all you can do (I am aware that some are modeling the CPU with caches, memory and everything to achieve 100% but thats very expensive and if you switch CPU's there is half a year worth of modeling down the drain)

The real world hard realtime systems often are built like: lets test it (with deadline miss triggering a failure) and if it works make sure we still have 10% of safety margin (which will later be melted down because of features ;-)