A fault tolerant computer system employing primary tasks and corresponding backup tasks. The system operates to provide fault tolerant operation even where uncontrolled external events may occur whose time of occurrence may affect task performance. For this purpose, external event data is stored for...http://www.google.com.au/patents/US5363503?utm_source=gb-gplus-sharePatent US5363503 - Fault tolerant computer system with provision for handling external events
