#STOCKFISH CHESS GPU CODE#
#STOCKFISH CHESS GPU FREE#

Hence, Stockfish uses a method which is computationally more efficient by doing a lookup in an array containing the candidate moves for the sliding pieces. However, the operation must be repeated for every attacking ray of every piece, which leads to a computationally intensive method for using in real time. An attacking ray of the piece is AND-ed with the bitboard of all the occupied squares, and a processor-level instruction called bitscan is used to find the first non-trivial bit of the computed result. Stockfish is an open-source Chess engine developed by Tord Romstad, Joona Kiiski, and Marco Costalba from Norway, with contributions from various programmers. Calculating their candidate moves on the fly is feasible using pre-calculated rays. Rooks, bishops and the queen can move an indefinite number of squares along a direction until they reach the edge of the board or until another piece obstructs their displacement. For this purpose, Stockfish has a bool Position::legal(Move m) method (position.cpp) which tests whether a pseudo-legal move is indeed legal. Finally, there are some more additional verifications, as of blocking pieces or discovered checks. The last 3 xxx are always different, even on exactly the same hardware.Stockfish is actually performing the checks after generating the candidates, and uses a Bitboard safe_destination(Square s, int step) (bitboard.cpp) method to ensure that the moves are not off the board. Kn/s: 123456 (only the first + second + third (here 123xxx is important to compare) Kn/s: 12345 (only the first + second (here 12xxx) is important to compare). On another hardware it could be 2000 (2xxx). Kn/s: 1234 (only the first (here the 1xxx) is important to compare).

You will never see exactly the same kn/s but that is today not important to compare. You only need to decide at the beginning if you want to compare tests with one core or more cores or maybe something like 2 vs 4 cores. After 1 minute is over you click the button again to stop the analysis and take the kn/s and run the test again with other engines on different hardware.

#STOCKFISH CHESS GPU FREE#

To measure and to compare the engine speed, you can use a free chess programm and then click the analysis button at the beginning of a game (starting position).

#STOCKFISH CHESS GPU CODE#

The fact that is scales so well with STM suggests to me that the SIMD code is suboptimal and could probably be improved to achieve better ILP.Īpple M1 CPU speed is very disappointingTo solve some answers and questions, take a look here: Stockfish seems to support Neon (ARM SIMD) but it's not really clear how it is utilized. Unfortunately, laptops/desktops with RTX. It's performance is comparable to much larger (and 4-5x hotter!) CPUs.įew additional observations: AMD seems to do really well in stockfish (for unclear reasons) and this benchmark really loves SMT. I built a desktop with a RTX GPU specifically to make use of Lc0 for chess (and also for some gaming on the side). My conclusion: no, M1's performance is not disappointing at all. Ah, and M1 is about 50% faster in the single-threaded variant than a 4.8ghz Intel Skylake refresh. 8-core desktop CPUs are considerably faster. Looking at the linked, M1 is faster than Tiger Lake. In a nutshell, M1 with it's 4 cores is 10% slower than top-shelf Intel mobile CPU with 8 cores while consuming 80% less power. ~ 1700 knodes/s for 1 thread using 35W of power ~ 13000 knodes/s for 16 threads using 65W of power ~ 2500 knodes/s for 1 thead using 5W of power ~ 12000 knodes/s for 8 threads using 15W of power Total: 1429 To make this configuration work, the motherboard was upgraded to a better choice with good support (and space) for two good-sized GPUs, and a larger 850W power supply. I ran the benchmarks with the settings suggested by (stockfish bench 128 NUMCORES 24 default depth) with the following results (power usage checked using Apple's powermetrics): This will give you top-notch results with either Fat Fritz or Leela, while still giving you a very capable processor able to push Stockfish at a good 13 million NPS.

Stockfish chess gpu