Lazy SMP

Tree searching technique in game theory

In combinatorial game theory, Lazy SMP is a parallelization technique for tree searching by launching the various depths used in iterative deepening on their respective threads (the technique used by Stockfish^[1]^[2]). Combined with a concurrent transposition table, the non-determinism of these threads leads to speed gains when different depths encounter games already searched by other threads. Lazy SMP was described, but not discovered, by Daniel Homan in a chess form.^[3]

References

^ "What is depth? - Stockfish FAQ". Stockfish Documentation.
^ "Stockfish 7". Stockfish.
^ Østensen, Emil. "A Complete Chess Engine Parallelized Using Lazy SMP" (PDF). Universitetet I Oslo.

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