Hardware thread-context switching

Numerous proposals have advanced fine-grained thread migration as a mechanism to address power, performance, reliability and memory coherence problems. However, exploiting conventional context switch mechanisms carries significant overhead, limiting the granularity of thread movement. Proposed is a novel hardware context switching circuit that enables low-overhead hardware thread migration between cores in a single-chip multiprocessor. This switching circuit supports multiple simultaneous thread switches and can store the context of both currently running and time-multiplexed threads. The circuit drastically reduces the direct cost of context switches.