I wonder how long it will be until someone designs a multi-core ARM processor with lockstep processing. One application for this is in mission-critical transac

I wonder how long it will be until someone designs a multi-core ARM processor with lockstep processing. One application for this is in mission-critical transaction processing where computing power is not the active limitation. Instead, the idea is that each core executes the same set of instructions with the same set of input data, and in the end if one disagrees with the other, the entire CPU rolls back the current transaction, takes itself out of the mesh, and alerts an operator... who, if it's an IBM mainframe, walks over with a new processor, yanks the old one, and replaces it. Hot. Downtime: none. Transactions lost: none. Sure, it would need more I/O capability + ECC, but still -- it's potentially a low-cost, low-power, highly reliable competitor to some of IBM's POWER and PowerPC processors.