— An increasing number of hardware failures can be attributed to device reliability problems that cause partial system failure or shutdown. In this paper we propose a scheme for improving reliability of a homogeneous chip multiprocessor (CMP) that also serves to improve manufacturing yield. Our solution centers on exploiting the natural redundancy that already exists in multi-core systems by using services from other cores for functional units that are defective in a faulty core. A micro-architectural modification allows a core on a CMP to use another core as a coprocessor to service any instruction that the former cannot execute correctly. This service is accessed to improve yield and reliability, but at the cost of some loss of performance. In order to quantify this loss we have used a cycleaccurate simulator to simulate the performance of a dual-core system with one or two cores sustaining partial failure. Our results indicate that when a large and sparingly-used unit such as a fl...