Online chess engines on powerul machines - what are the options?

[zullil]

So now i't trying to find absolute best move in the following position:

[d]r1bq1rk1/pppp1ppp/2n2n2/8/3BP3/2N5/PPP2PPP/R2QKB1R w KQ - 1 8

I think there are two serious moves: Be2 and Bxf6. I'm running analysis on my machine with latest Stockfish dev (1CPU, 4096MB hash, Analysis Contempt: Off) and after 50 hours he favours Be2. But... now, at depth 59, he's been contemplating Bxf6 (for the next 10 hours). I'm afraid I don't have enough computing power (and time ) to go beyond depth 60.

Can someone provide deep analysis of this position with latest Stockfish with Analysis Contempt set to Off? And maybe Leela (with current best ID 11041) can give some hint there.

Here's what Cfish-dev has (Analysis Contempt = off, MultiPV=2):

+0.53 8. Be2 d6 9. Qd2 Nxd4 10. Qxd4 Bd7 11. O-O-O Bc6 12. Bc4 Nd7 13. f3 Re8 14. h4 Ne5 15. Be2 a6 16. Qd2 b5 17. g4 b4 18. Nd5 Bxd5 19. Qxd5 Qf6 20. g5 Qf4+ 21. Qd2 Qxd2+ 22. Kxd2 Nd7 23. Ke3 Re5 24. Ra1 Ra5 25. Bd3 Rb8 26. f4 Nc5 27. h5 h6 28. g6 f5 29. Bc4+ Kf8 30. exf5 Na4 31. b3 Nc3 32. Be6 Nd5+ 33. Bxd5 Rxd5 34. f6 Re8+ 35. Kf3 gxf6 36. a3 bxa3 37. Rxa3 Rc5 38. Rha1 Rxc2 (depth 53, 10:55:55)

+0.44 8. Bxf6 Qxf6 9. Bd3 Ne5 10. Be2 Ng6 11. Qd2 c6 12. f3 Nf4 13. Bf1 Rd8 14. O-O-O d6 15. a4 Ne6 16. h4 Nc7 17. Kb1 d5 18. exd5 Nxd5 19. Bc4 Be6 20. Bxd5 Bxd5 21. Qg5 Qxg5 22. hxg5 Be6 23. Kc1 Rxd1+ 24. Rxd1 Kf8 25. Rh1 Kg8 26. a5 Rd8 27. Rh4 Bf5 28. Ne2 Kf8 29. b4 Bg6 30. Nd4 Rd6 31. Kb2 Rd5 32. Kc3 Ke7 33. a6 bxa6 34. f4 Kd6 (depth 53, 10:55:55)

[Karol Majewski]

And here is latest Stockfish after 82 hours on 1CPU. I had to abort the search.

r1bq1rk1/pppp1ppp/2n2n2/8/3BP3/2N5/PPP2PPP/R2QKB1R w KQ - 1 8

82:29.13 8.Be2 (głębokość 59, 1/40), 423,9G pozycji (1,4M na sekundę), 2,6M końcówek
0.00: +1.36/3 8.e5 Nxd4 9.Qxd4
0.00: +2.39/4 8.e5 b6 9.exf6 Nxd4 10.Qxd4
0.00: +2.21/5 8.e5 b5 9.Nxb5 Nxd4 10.Nxd4
0.00: +0.33/6 8.Be2 d6 9.O-O Nxd4 10.Qxd4 Re8
0.00: +0.12/7 8.Be2 d6 9.O-O Nxd4 10.Qxd4 Bd7 11.Qd3
0.00: -0.09/8 8.Be2 d6 9.O-O Nxd4 10.Qxd4 Bd7 11.Qd3 Re8
0.00: +0.27/9 8.Be2 Nxd4 9.Qxd4 d6 10.O-O-O Bd7 11.f3 Re8 12.Kb1
0.00: +0.37/10 8.Be2 Nxd4 9.Qxd4 d6 10.O-O-O Bd7 11.f3 h6 12.Qd2 Re8 13.Kb1
0.00: +0.70/11 8.Be2 d6 9.f3 Bd7 10.Bf2 h6 11.Qd2 Re8 12.O-O-O Ne5 13.Kb1
0.00: +0.43/12 8.Be2 d6 9.f3 Nxd4 10.Qxd4 Re8 11.O-O-O a5 12.Qf2 Bd7 13.Kb1 Re5 14.Rhe1 h6
0.00: +0.45/13 8.Bxf6 Qxf6 9.Bd3 d6 10.Nd5 Qxb2 11.O-O a6 12.Nxc7 Rb8 13.Nd5 Qe5 14.Rb1 Be6
0.00: +0.33/14 8.Be2 Re8 9.Bxf6 Qxf6 10.O-O d6 11.Nd5 Qd8 12.Qd3 Be6 13.Rad1 Bxd5 14.exd5 Ne5 15.Qg3
0.00: +0.67/15 8.Be3 Re8 9.Bc4 d6 10.f3 Be6 11.Bxe6 Rxe6 12.Qd2 a5 13.O-O Re8 14.Rad1 h6 15.b3 b6
0.00: +0.48/16 8.Be3 Re8 9.Bc4 Ne5 10.Be2 Nc6 11.Bf3 d6 12.O-O Bd7 13.a4 a6 14.Re1 b6 15.Bg5 h6 16.Bh4 Nb4 17.Qd2 Bc6
0.01: +0.32/17 8.Be3 Re8 9.Bc4 Ne5 10.Bb3 Neg4 11.Qe2 Nxe3 12.Qxe3 b5 13.f3 c6 14.a3 a5 15.O-O Ba6 16.Qc5 Qc7
0.01: +0.55/18 8.Bxf6 Qxf6 9.Bd3 d6 10.Qd2 Be6 11.f4 Nb4 12.f5 Bd7 13.O-O Rae8 14.Bc4 Nxc2 15.Rad1 Nb4 16.a3 Nc6 17.Bd5 Ne5 18.Bxb7
0.03: +0.55/19 8.Bxf6 Qxf6 9.Bd3 Re8 10.O-O Ne5 11.f4 Nxd3 12.cxd3 b5 13.Kh1 b4 14.Nd5 Qd6 15.Ne3 Qb6 16.Re1 Ba6 17.Nf5
0.04: +0.50/20 8.Bxf6 Qxf6 9.Bd3 Nb4 10.O-O Nxd3 11.cxd3 d6 12.d4 Bd7 13.f4 Rae8 14.f5 Bc6 15.Qd3 Qh4 16.Rac1 Bxe4 17.Nxe4 Rxe4 18.Rxc7
0.04: +0.44/21 8.Bxf6 Qxf6 9.Bd3 d6 10.Qd2 Be6 11.f4 Qd4 12.O-O-O Nb4 13.Kb1 Nxd3 14.Qxd3 Qxd3 15.Rxd3 Rae8 16.Re1 f5 17.e5 dxe5 18.Rxe5 Bc4 19.Rd4 Be6 20.Rc5
0.06: +0.49/22 8.Bxf6 Qxf6 9.Bd3 Ne5 10.Qd2 Nxd3+ 11.Qxd3 d6 12.Nd5 Qd8 13.O-O-O Be6 14.Kb1 Re8 15.f3 a5 16.Rhe1 Bxd5 17.Qxd5 a4 18.a3 Qd7 19.f4 Qc6
0.08: +0.57/23 8.Bxf6 Qxf6 9.Bd3 Ne5 10.Qd2 Nxd3+ 11.Qxd3 d6 12.Nd5 Qd8 13.O-O-O Be6 14.Kb1 Re8 15.Nc3 a5 16.f4 Bg4 17.Rde1 Be6 18.h3 Bd7 19.a3 h6 20.Qg3 b5
0.13: +0.39/24 8.Bxf6 Qxf6 9.Bd3 Ne5 10.Be2 d6 11.Qd2 Be6 12.f3 Nc4 13.Bxc4 Bxc4 14.O-O-O b5 15.Qd4 Qxd4 16.Rxd4 Rab8 17.b3 Be6 18.b4 f5 19.Kb2 g6 20.exf5 Rxf5
0.14: +0.42/25 8.Bxf6 Qxf6 9.Bd3 Ne5 10.Be2 d6 11.Qd2 Be6 12.f3 Nc4 13.Bxc4 Bxc4 14.O-O-O b5 15.Qd4 Qxd4 16.Rxd4 Rfb8 17.b3 Be6 18.Re1 a6 19.e5 dxe5 20.Rxe5 b4 21.Na4 a5 22.Nc5
0.17: +0.40/26 8.Bxf6 Qxf6 9.Bd3 Ne5 10.Be2 d6 11.Qd2 Be6 12.f3 Nc4 13.Bxc4 Bxc4 14.b3 Be6 15.O-O Rae8 16.f4 Bd7 17.Rae1 Bc6 18.Qd3 h6 19.Nd5 Qd8 20.f5 b6 21.f6 Bxd5 22.Qxd5
0.20: +0.49/27 8.Bxf6
0.34: +0.47/27 8.Be3 Re8 9.Bc4 d6 10.f3 a6 11.O-O Be6 12.Bb3 Ne5 13.Qd2 b5 14.Bxe6 fxe6 15.Bf2 b4 16.Na4 a5 17.b3 Qe7 18.Rae1 h6 19.Rd1 Rad8 20.Qe3 c5 21.Nb6
0.53: +0.45/28 8.Be3 Re8 9.Qf3 Ne5 10.Qg3 Neg4 11.O-O-O Nxe3 12.Qxe3 c6 13.Qd4 Qc7 14.Kb1 b5 15.f3 Bb7 16.Be2 Rad8 17.Qd6 Qxd6 18.Rxd6 Re6 19.Rhd1 Rxd6 20.Rxd6 Ne8 21.Rd4 Nc7 22.f4
1.01: +0.36/29 8.Be3 Re8
1.16: +0.48/29 8.Bxf6 Qxf6 9.Bd3 Ne5 10.Qd2 Nxd3+ 11.Qxd3 b6 12.Qg3 d6 13.O-O-O Bb7 14.f3 Rfe8 15.Kb1 a5 16.Nb5 Re7 17.Rhe1 Bc6 18.Nc3 Ree8 19.Nd5 Bxd5 20.Rxd5 Qg6 21.Qf2 c6 22.Rdd1 c5 23.Qg3 Qxg3 24.hxg3
1.31: +0.48/30 8.Bxf6
1.57: +0.46/30 8.Be2 Re8 9.f3 d5 10.Bxf6 Qxf6 11.Qxd5 Be6 12.Qc5 Nd4 13.O-O-O Nxe2+ 14.Nxe2 Bxa2 15.Rd2 Qa6 16.Qa3 Qxa3 17.bxa3 Rad8 18.Rhd1 Rxd2 19.Rxd2 Be6 20.Kb2 Kf8 21.Nd4 Ke7 22.Rd1 c5 23.Nb5 a5 24.Nc7 Rd8 25.Rxd8 Kxd8 26.Nxe6+ fxe6
2.09: +0.59/31 8.Be2 Re8 9.f3 d5 10.Bxf6 Qxf6 11.Qxd5 Be6 12.Qc5 Nd4 13.O-O-O Nxe2+ 14.Nxe2 Bxa2 15.Rd2 Qa6 16.Nd4 Bc4 17.Qa3 Qxa3 18.bxa3 Rad8 19.Rhd1 Rd6 20.Kb2 Kf8 21.Kc3 b5 22.Nb3 Rxd2 23.Nxd2 Be6 24.Kb4 a6
2.30: +0.51/32 8.Be2
2.57: +0.58/32 8.Bxf6 Qxf6 9.f3 Re8 10.Qd2 d5 11.Qxd5 Be6 12.Qc5 Qf4 13.Bd3 Rad8 14.O-O Nd4 15.Kh1 b6 16.Qa3 a5 17.Rad1 Rd6 18.b3 Red8 19.Qc1 Qxc1 20.Rxc1 Rc6 21.Nb5 Nxb5 22.Bxb5 Rc3 23.Bd3 g5 24.Rcd1 Kg7 25.e5 h5 26.f4
3.05: +0.75/33 8.Bxf6
3.50: +0.73/33 8.f3 Re8 9.Qd2 d5 10.Bxf6 Qxf6 11.Qxd5 Be6 12.Qc5 Qf4 13.Bd3 Rad8 14.O-O Nd4 15.Kh1 b6 16.Qa3 a5 17.Rae1 c6 18.b3 h6 19.Qc1 Qxc1 20.Rxc1 b5 21.e5 b4 22.Ne4 Bf5 23.f4 Bxe4 24.Bxe4 Ne2 25.Bxc6 Re7 26.Rfd1 Rxd1+ 27.Rxd1 Nxf4
5.15: +0.64/34 8.f3 Re8
6.25: +0.71/34 8.Be2 Qe7 9.Bxf6 Qxf6 10.Qd2 d6 11.f4 Qd4 12.O-O-O Qxd2+ 13.Rxd2 Be6 14.Re1 Rfe8 15.Kb1 f6 16.a3 Rad8 17.b3 g6 18.Kb2 Kg7 19.Nb5 Re7 20.Bf3 Bf7 21.Nc3 f5 22.e5 dxe5 23.Rxd8 Nxd8 24.fxe5 Rd7 25.h4
7.45: +0.68/35 8.f3 Re8 9.Qd2 d5 10.O-O-O dxe4 11.Bb5 exf3 12.gxf3 Bf5 13.Qf4 Bg6 14.Bxf6 Qxf6 15.Qxf6 gxf6 16.Nd5 Red8 17.Bxc6 bxc6 18.Ne7+ Kf8 19.Nxc6 Re8 20.Rd7 Re2 21.Nd4 Re7 22.Rxe7 Kxe7 23.b4 Kd7 24.Rd1 Rg8 25.Kb2 Bh5 26.Kc3 Rg2 27.Rd2 Rxd2 28.Kxd2 Kd6 29.Ke3 Bg6 30.c3
11.56: +0.76/36 8.f3 Re8 9.Qd2 Nxd4 10.Qxd4 d6 11.O-O-O Qe7 12.g4 Bd7 13.g5 Nh5 14.h4 Qe5 15.Qxe5 Rxe5 16.Nd5 Rc8 17.b3 Ree8 18.Kb2 g6 19.a4 Kg7 20.Bc4 Be6 21.b4 Bxd5 22.Bxd5 Nf4 23.Bb3 f6 24.Bc4 Re5 25.Rhg1 Rce8 26.gxf6+ Kxf6
14.12: +0.69/37 8.f3 Re8 9.Qd2 Nxd4 10.Qxd4 c6 11.O-O-O Qc7 12.Qd6 Qxd6 13.Rxd6 b5 14.h4 Re7 15.a3 a5 16.a4 b4 17.Ne2 Bb7 18.Nf4 Rd8 19.b3 Ne8 20.Rd1 Nc7 21.Bd3 d5 22.Kb2 g6 23.g4 dxe4 24.Bxe4 Rxd1 25.Rxd1 Kf8 26.Rd6 Ne6 27.Nxe6+ Rxe6 28.Rxe6
15.18: +0.79/38 8.f3 Re8 9.Qd2 Nxd4 10.Qxd4 c6 11.O-O-O Qc7 12.Qd6 Qxd6 13.Rxd6 b5 14.h4 Rd8 15.a4 Ne8 16.Rd4 a6 17.Be2 Nc7 18.Rd6 Kf8 19.a5 Bb7 20.Rhd1 Ke7 21.b4 Nd5 22.Nxd5+ Kxd6 23.Nb6+ Ke6 24.Nxa8 Rxa8 25.Kd2 Rc8 26.c4 bxc4 27.Bxc4+ d5 28.Bb3 c5 29.exd5+ Bxd5 30.Bxd5+ Kxd5 31.Kc3+ Kc6
22.29: +0.65/39 8.f3 Re8 9.Qd2 Nxd4 10.Qxd4 d6 11.O-O-O Qe7 12.g4 Bd7 13.h4 Qe5 14.Qd2 Bc6 15.Kb1 Rad8 16.Bh3 Nd7 17.g5 Nb6 18.b3 d5 19.Rhe1 Qg3 20.exd5 Rxe1 21.Qxe1 Qxe1 22.Rxe1 Nxd5 23.Nxd5 Bxd5 24.Re7 Bxf3 25.Rxc7 h6 26.Bc8 b6 27.Bb7 Rd1+ 28.Kb2 Bxb7 29.Rxb7 hxg5 30.hxg5 Rg1 31.Rxa7
24.56: +0.71/40 8.f3 Re8 9.Qd2 Nxd4 10.Qxd4 d6 11.O-O-O Qe7 12.g4 Bd7 13.h4 Qe5 14.Qxe5 Rxe5 15.Rg1 Rd8 16.Be2 Ree8 17.b3 g6 18.Kb2 Kg7 19.Bc4 h6 20.Rh1 g5 21.b4 Rh8 22.a4 a6 23.b5 axb5 24.axb5 Be6 25.Bxe6 fxe6 26.hxg5 hxg5 27.Rxh8 Kxh8 28.b6
36.57: +0.72/41 8.f3 Re8 9.Qd2 Nxd4 10.Qxd4 d6 11.O-O-O Be6 12.Rg1 c6 13.Qxd6 Qa5 14.Qa3 Qc7 15.Be2 Qxh2 16.Kb1 Qe5 17.g3 Qc7 18.Qc5 h6 19.f4 Qb6 20.Qxb6 axb6 21.a4 b5 22.axb5 Nxe4 23.Nxe4 Ba2+ 24.Kc1 Rxe4 25.Bd3 Re3 26.Kd2 Re7 27.Rge1 Rxe1 28.Rxe1 cxb5 29.Bxb5 Rd8+ 30.Ke3 Bd5
41.59: +0.55/42 8.f3 d5
47.40: +0.55/42 8.Be2 Re8 9.f3 d5 10.Bxf6 Qxf6 11.Nxd5 Qxb2 12.Nxc7 Rd8 13.Qc1 Qc3+ 14.Kf2 Rd2 15.Rd1 Rxc2 16.Qe3 Rb8 17.Qxc3 Rxc3 18.Rac1 Rxc1 19.Rxc1 Bd7 20.Rd1 Rd8 21.f4 Kf8 22.e5 Ke7 23.a3 Be6 24.Rxd8 Nxd8 25.Ke3 f6 26.Nxe6 Kxe6 27.Bc4+ Ke7 28.g3 fxe5 29.fxe5 Ne6 30.Ke4 g6 31.g4
1:00.30: +0.68/43 8.Be2 Re8 9.f3 d5 10.Bxf6 Qxf6 11.Nxd5 Qe5 12.O-O Be6 13.c4 f5 14.Bd3 Rad8 15.Kh1 f4 16.Qb3 b6 17.Rad1 Nd4 18.Qc3 c5 19.Qa3 Rd7 20.b4 Rc8 21.bxc5 bxc5 22.Qa5 Rf7 23.Qd2 g5 24.Rb1 Kg7 25.Rb2 Rd8 26.Qa5 Nc6 27.Qa3 g4 28.Rd1 Rfd7 29.fxg4 Bxg4
1:11.31: +0.64/44 8.Be2 d6 9.Qd3 Re8 10.O-O-O Nxd4 11.Qxd4 Bd7 12.f3 Qe7 13.g4 Qe5 14.h4 Qxd4 15.Rxd4 Be6 16.b3 a6 17.Kb2 g6 18.Bc4 Kg7 19.h5 Bxc4 20.h6+ Kf8 21.Rxc4 Rac8 22.Rd4 g5 23.Rdd1 Ke7 24.Rhf1 Kf8 25.a4 Re6 26.Rh1 Ree8 27.Ka3 Ke7 28.Rhf1 Kd7 29.Kb2 Rb8 30.a5 Kc6 31.b4
1:21.39: +0.61/45 8.Be2 d6 9.f3 Be6 10.Bf2 d5 11.exd5 Nxd5 12.Nxd5 Bxd5 13.O-O Be6 14.Bd3 Ne5 15.Be4 c6 16.Re1 Qxd1 17.Raxd1 Rfd8 18.Rxd8+ Rxd8 19.Bxa7 f5 20.Bxf5 Nxf3+ 21.gxf3 Bxf5 22.Re7 Rd7 23.Rxd7 Bxd7 24.Be3 Kf7 25.Kf2 Bf5 26.c3 Bc2 27.Bc5 b5 28.b3 Ke6 29.Ke3 Kd5 30.Be7 Bb1 31.a4 Bc2 32.a5 Bxb3
1:56.23: +0.69/46 8.Be2 Qe7 9.f3 Re8 10.Bf2 d5 11.exd5 Nb4 12.d6 Qe5 13.O-O Bf5 14.Bb5 Red8 15.Ba4 Rxd6 16.Qc1 Qa5 17.Re1 Bd7 18.Bb3 Be6 19.Bxe6 Rxe6 20.Rxe6 fxe6 21.a3 Nbd5 22.Qg5 Qa6 23.Nxd5 exd5 24.Re1 Qd6 25.Qf5 Re8 26.Rxe8+ Nxe8 27.Qc8 Qc6 28.b4 b6 29.Bd4 Qg6 30.Qa8 Kf8 31.Qxd5 Qxc2 32.Qd7 Qb1+ 33.Kf2 Qc2+ 34.Kg3 Qg6+ 35.Kf2
2:27.18: +0.63/47 8.Be2 d6 9.f3 Be6 10.Bf2 d5 11.exd5 Nxd5 12.Nxd5 Bxd5 13.O-O Qg5 14.h4 Qf5 15.Bd3 Qh5 16.Re1 Rad8 17.Qe2 f6 18.Rad1 Rfe8 19.Qd2 Ne5 20.Bg3 Nxd3 21.Qxd3 Rxe1+ 22.Rxe1 Qg6 23.Qxg6 hxg6 24.Rd1 Rd7 25.c4 Bc6 26.Rxd7 Bxd7 27.Bxc7 Bf5 28.a3 Kf7 29.b3 Bc2 30.b4 Bb3 31.c5 g5 32.hxg5 fxg5 33.Kf2
2:39.38: +0.60/48 8.Be2 d6 9.f3 Be6 10.Bf2 d5 11.exd5 Nxd5 12.Nxd5 Bxd5 13.O-O Qg5 14.h4 Qf5 15.Bd3 Qh5 16.Re1 Rad8 17.Qe2 f6 18.Rad1 Rfe8 19.Qd2 Ne5 20.Bg3 Rd7 21.Qf2 Nxd3 22.Rxd3 Rxe1+ 23.Qxe1 Bc6 24.Rxd7 Bxd7 25.Kh2 Qc5 26.Qd2 Qc6 27.Qa5 a6 28.Bxc7 Be6 29.c3 Qb5 30.Qxb5 axb5 31.a3 Kf7 32.Kg3 Bd5 33.Bd6 Be6 34.Kf2 h6 35.Ke3
3:36.07: +0.59/49 8.Be2 d6 9.Qd3 Nxd4 10.Qxd4 Bd7 11.O-O-O Re8 12.f3 Qe7 13.g4 Bc6 14.Kb1 a6 15.g5 Nd7 16.h4 Qe5 17.Qf2 Qc5 18.Qh2 b5 19.Nd5 Ne5 20.Nxc7 Bxe4 21.fxe4 Qxc7 22.h5 Rac8 23.Rd2 Nc4 24.Bxc4 Qxc4 25.Rxd6 Qxe4 26.Rhd1 Qe1 27.h6 Qe2 28.Qxe2 Rxe2 29.Rxa6 Rg2 30.Rad6 gxh6 31.gxh6 Kf8 32.R6d2 Rxd2 33.Rxd2 Rc5 34.c3 Rh5 35.Kc2 Rxh6
4:22.21: +0.68/50 8.Bxf6 Qxf6 9.Qd2 d5 10.Qxd5 Rd8 11.Qc5 Qf4 12.Bd3 Be6 13.O-O Ne5 14.Rad1 b6 15.Qa3 Nxd3 16.Rxd3 Rxd3 17.cxd3 c5 18.Qa4 h6 19.Rd1 Qg5 20.Qc6 Qd8 21.e5 Rc8 22.Qe4 Qd4 23.Kf1 g5 24.f3 Kg7 25.a3 Rd8 26.Qxd4 Rxd4 27.Kf2 Kg6 28.g4 Bb3 29.Rd2 f6 30.exf6 Kxf6 31.Ke3 a5 32.Ne2 Rd8 33.Ng3 Ke5 34.Nf5 Kf6 35.d4 Re8+ 36.Kd3 Rd8
4:45.04: +0.59/51 8.Bxf6 Qxf6
6:33.20: +0.51/51 8.Be2 d6 9.Qd3 Nxd4 10.Qxd4 Bd7 11.O-O-O Re8 12.f4 Bc6 13.Bf3 Nd7 14.g3 a6 15.Rhe1 Qf6 16.Qd2 Qe6 17.Kb1 Qc4 18.g4 b5 19.h4 Nb6 20.Qd3 f6 21.b3 Qxd3 22.cxd3 Bb7 23.Ne2 c5 24.g5 fxg5 25.hxg5 a5 26.Bh5 Re7 27.f5 a4 28.f6 Re5 29.Rg1 c4 30.dxc4 axb3 31.axb3 Bxe4+ 32.Kc1 Ra1+ 33.Kb2 Rxd1 34.Rxd1 Rxg5 35.f7+ Kf8 36.Nf4 Re5 37.Rxd6
7:16.03: +0.60/52 8.Be2 d6 9.Qd3 Nxd4 10.Qxd4 Bd7 11.O-O-O Re8 12.f4 Bc6 13.Bf3 Nd7 14.Qd2 Nc5 15.Rhe1 Qf6 16.g3 Rad8 17.Kb1 a5 18.Nd5 Bxd5 19.Qxd5 Qe6 20.Qd4 b6 21.a3 Qh3 22.Qc3 h6 23.Rd2 Qe6 24.Rd5 Qh3 25.Rdd1 Qc8 26.Re2 Qh3 27.Qd2 f6 28.Ree1 Kh7 29.Qc3 Qc8 30.b3 Qh3 31.e5 fxe5 32.Bc6 Re6 33.Bd5 Rg6 34.fxe5 Qxh2
9:16.38: +0.55/53 8.Be2 d6 9.Qd2 Nxd4 10.Qxd4 Bd7 11.O-O-O Re8 12.f3 Qe7 13.h4 Bc6 14.g4 a6 15.g5 Nh5 16.Bc4 Qe5 17.Qf2 Nf4 18.Kb1 Rab8 19.Qa7 Ne6 20.Qg1 Qc5 21.Qxc5 dxc5 22.Bd5 Bxd5 23.Nxd5 b5 24.c3 Rbd8 25.Kc2 c6 26.Ne3 Kf8 27.b3 f6 28.gxf6 gxf6 29.Ng4 Ke7 30.Nh6 Rxd1 31.Nf5+ Kf7 32.Rxd1 Rd8 33.Rxd8 Nxd8 34.Kd3 Ne6 35.Ke3 Kg6 36.Nd6
10:37.45: +0.61/54 8.Be2 d6 9.Qd2 Nxd4 10.Qxd4 Bd7 11.O-O-O Re8 12.f4 Bc6 13.Bf3 Nd7 14.Qd2 Nc5 15.Rhe1 Qf6 16.g3 Rad8 17.Kb1 b6 18.Nd5 Bxd5 19.Qxd5 Rd7 20.Re3 Rdd8 21.a3 a5 22.Ree1 Qe6 23.Qd4 Qc8 24.Qc3 Qh3 25.Rd2 Qc8 26.Rd5 Qh3 27.Rdd1 h6 28.Rd2 Qe6 29.Red1 Qe7 30.Re2 Qe6 31.Re3 Qc8 32.h4 Qe6 33.b4 axb4 34.axb4 Na4 35.Qb3
13:33.09: +0.61/55 8.Be2 d6 9.Qd2 Nxd4 10.Qxd4 Bd7 11.O-O-O Re8 12.f4 Bc6 13.Bf3 Nd7 14.Qd2 Nc5 15.Rhe1 Qf6 16.g3 Qh6 17.Qf2 Qg6 18.Qd4 Qh6 19.Re2 b6 20.Nd5 Rac8 21.a3 Qh3 22.Qf2 Bxd5 23.Rxd5 Qh6 24.e5 dxe5 25.Rdxe5 Rxe5 26.Rxe5 Qd6 27.Qd2 Qxd2+ 28.Kxd2 Rd8+ 29.Kc3 Kf8 30.b4 Ne6 31.Rh5 h6 32.Rd5 Rxd5 33.Bxd5 Ke7 34.Kc4 g6 35.b5 Kd6 36.Bxe6 Kxe6 37.g4
15:45.56: +0.61/56 8.Be2 d6 9.Qd2 Nxd4 10.Qxd4 Bd7 11.O-O-O Re8 12.f4 Bc6 13.Bf3 Nd7 14.Qd2 Nc5 15.Rhe1 Qf6 16.g3 Rad8 17.Nd5 Bxd5 18.Qxd5 b6 19.Kb1 Rd7 20.Re3 Rdd8 21.Rde1 a5 22.a3 Qe6 23.Qc6 Qc8 24.Rd1 h6 25.b4 Ne6 26.Be2 Qb8 27.Bb5 Re7 28.Kb2 Qa7 29.c3 Ra8 30.Kb1 Nd8 31.Qd5 Ne6 32.Bc6 b5 33.Rde1 Rb8 34.Kb2 g6 35.e5 dxe5 36.Qxe5 axb4
24:29.10: +0.55/57 8.Be2 d6 9.f3 Be6 10.Bf2 d5 11.Nxd5 Nxd5 12.exd5 Bxd5 13.O-O Be6 14.Bd3 Qf6 15.c3 Ne5 16.Be4 Ng6 17.Qc2 Rad8 18.Bxb7 Qg5 19.Rad1 Nf4 20.Bg3 Nh5 21.f4 Qb5 22.Rxd8 Rxd8 23.Bh4 Rd6 24.Be4 Bxa2 25.Qf2 Re6 26.Bf3 Nxf4 27.Qxa7 Bd5 28.Bxd5 Nxd5 29.c4 Qb6+ 30.Qxb6 Nxb6 31.b3 f6 32.Bg3 Re3 33.Rb1 Re7 34.Kf2 Nd7 35.Bxc7 Nc5 36.Ba5 Kf7 37.Kf3 Rd7 38.Bb4 Rd3+ 39.Ke2 Rxb3 40.Rxb3 Nxb3 41.Kd3
53:02.27: +0.54/58 8.Be2 d6 9.Qd3 Nxd4 10.Qxd4 Bd7 11.O-O-O Re8 12.f3 Qe7 13.g4 Bc6 14.Rhg1 Nd7 15.g5 Qe5 16.Qxe5 Nxe5 17.a4 a6 18.b3 Ng6 19.Kd2 Rad8 20.Bc4 Re5 21.Rdf1 d5 22.exd5 Bxd5 23.Nxd5 Nf4 24.Kc1 Nxd5 25.Re1 Rf5 26.Bd3 Rf4 27.Be4 c6 28.Rd1 Re8 29.Bxd5 cxd5 30.Rxd5 Rxf3 31.Rgd1 Rf2 32.R5d2 Rxd2 33.Rxd2 Kf8 34.Kb2 Re7 35.Rd8+ Re8 36.Rxe8+ Kxe8 37.Kc3 Ke7 38.a5 f5 39.gxf6+ Kxf6
82:29.13: +0.45/59 8.Be2 d6

[zullil]

Stopping here:

+0.55 8. Be2 d6 9. Qd2 Nxd4 10. Qxd4 Re8 11. O-O-O Bd7 12. f4 Bc6 13. Bf3 Nd7 14. Rhe1 Qh4 15. Qd2 a6 16. g3 Qh3 17. Re2 Qe6 18. Re3 a5 19. Kb1 Nc5 20. Rde1 Qd7 21. Nd5 b6 22. a3 Bxd5 23. Qxd5 Rab8 24. Rd1 Re7 25. b3 h6 26. Kc1 Rd8 27. e5 dxe5 28. Rxe5 Qxd5 29. Rdxd5 Rde8 30. Rxe7 Rxe7 31. Kd2 f6 32. b4 axb4 33. axb4 Ne4+ 34. Bxe4 Rxe4 35. Rd7 Rxb4 36. Rxc7 Re4 37. f5 (depth 55, 14:38:17)

+0.47 8. Bxf6 Qxf6 9. Bd3 d6 10. Qd2 Ne5 11. Be2 Be6 12. f3 Nc4 13. Bxc4 Bxc4 14. O-O-O b5 15. Qd4 Qf4+ 16. Kb1 a6 17. h4 Be6 18. h5 h6 19. Ne2 Qe5 20. g4 Qxd4 21. Rxd4 a5 22. Nf4 a4 23. Re1 Rfe8 24. Nd5 Bxd5 25. Rxd5 Reb8 26. e5 dxe5 27. Rdxe5 Ra6 28. a3 Rf6 29. R1e3 c6 30. b3 g6 31. Kb2 Kg7 32. Rd3 gxh5 33. Rxh5 Re8 34. bxa4 bxa4 35. Rc5 Re2 36. Rc4 Rf2 37. Rxa4 R6xf3 (depth 55, 14:38:17)

[Karol Majewski]

Thanks. BTW, what's the relation between depth and number of threads? Is depth 55 on 20CPU deeper than depth 59 on 1CPU? I've never understood paralell search in SF.

[zullil]

Thanks. BTW, what's the relation between depth and number of threads? Is depth 55 on 20CPU deeper than depth 59 on 1CPU? I've never understood paralell search in SF.

With all the various extensions and reductions, "depth" is a problematic term. Maybe best to replace "depth" with "iteration". Stockfish also reports "seldepth" (selective depth), but not all GUIs display it.

Parallel search with Lazy SMP muddies the waters further.

Maybe a Stockfish search expert can address the question "Is depth 55 on 20CPU deeper than depth 59 on 1CPU?"

My search to "depth 55" was using MultiPV = 2, so that also affects the answer.