bsamseth / Goldfish

Goldfish - Stockfish's very distant and not so bright cousin - a UCI chess engine

MIT License

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Use NegaScout in place of PVS and add TTable in quiescense search #21

Closed bsamseth closed 5 years ago

bsamseth commented 5 years ago

Minor speed improvement. Nothing major, do not expect big changes in eval. But still, should be superior, and does not add notable complexity.

v1.7.1

Total time (ms) : 5915 Nodes searched : 6398514 Nodes/second : 1081805

v1.7.0

Total time (ms) : 6192 Nodes searched : 7000990 Nodes/second : 1130651

coveralls commented 5 years ago

Coverage remained the same at 86.027% when pulling 7f9a1bee14540a7a2f4f6a7487fa0be2eafd4344 on nega-scout into d41313ec22b6ceae48cc596d1c063ea6e06564ca on master.

bsamseth commented 5 years ago

With the addition of ttable in quiescense we have a stastistically significant improvement.

v1.7.1

Times (ms): [5973 5959 5714 5963 5863 6019 5671 5914 6051 6026] Average: 5.9153e+03 Std: 1.2324e+02 CI 95%: [5.6738e+03, 6.1568e+03] Nodes constant: TRUE Nodes: 6137342 Nodes/second: 1.0375e+03 CI 95%: [1.0817e+03, 9.9683e+02]

v1.7.0

Times (ms): [6931 7072 7091 6792 6577 6563 6502 6602 6277 6537] Average: 6.6944e+03 Std: 2.5318e+02 CI 95%: [6.1982e+03, 7.1906e+03] Nodes constant: TRUE Nodes: 7000990 Nodes/second: 1.0458e+03 CI 95%: [1.1295e+03, 9.7363e+02]

bsamseth commented 5 years ago

No notable change in ELO. Preliminary testing suggests a minor (~5 ELO) downgrade. Might be random, might be a need for more Mb in tt due to more positions being stored. Merging for now.