Soft error detection by using tag comperator in microprocessors

Soft errors caused by high energy particle strikes are becoming an increasingly important problem in microprocessor design. With increasing transistor density and die sizes soft errors are expected to be a larger problem in the near future. Recovering from these unexpected faults may be possible by reexecuting some part of the program if the error can be detected. Therefore it is important to come up with new techniques to detect soft errors. Modern microprocessors employ out-of-order execution and dynamic scheduling logic. Comparator circuits used to keep track of data dependencies are usually idle and can be used to detect the soft errors on the stored tag information inside the issue queue. In this thesis, we propose various schemes to exploit on-chip comparators to detect transient faults. Keywords: Comparators, computer architecture, error detection coding, fault tolerance, microprocessors