Design considerations for a single-chip fault tolerant VLSI microprocessor

A design approach is presented for a general-purpose VLSI fault tolerant microprocessor, with redundancy designed into the internal chip architecture. The design features are internal automatic state storage and rollback/retry mechanism and a microprogrammed ALU design. The reliability of the design is estimated using a system model of reliability behaviour, and is compared with that of other fault tolerant design strategies. Finally, the effect of the fault tolerance on processor performance is discussed.