The Goering Gambit

[Uri Blass]

Senpai needs a long time to find
18.e5 some moves after the root so if this position proves a problem with free source engines then it seems that the problem is mainly not with stockfish or gull but with senpai.

[d]r1bq4/ppp1r2Q/1b1p1kp1/n5N1/3PP3/8/P4PPP/R4RK1 w - - 0 18

Senpai1.0_sse42:
1/2 00:00 35 118 -6.09 18.Qh4 Bxd4
2/8 00:00 356 1k -4.67 18.Qh4 Bd7
3/12 00:00 1k 4k -4.16 18.Qh4 Nc4 19.d5
4/16 00:00 2k 194k -4.31 18.Qh4 Nc4 19.Rac1 Qg8
5/20 00:00 8k 826k -4.18 18.Qh4 Kg7 19.Rfd1 Qh8 20.Nh7
6/20+ 00:00 9k 948k -4.08 18.Qh4 Nc6 19.d5 Kg7
6/20+ 00:00 10k 1,002k -3.98 18.Qh4 Re6
6/20 00:00 12k 1,209k -4.10 18.Qh4 Qe8 19.d5 Kg7 20.Rac1 Kg8
7/20 00:00 13k 655k -4.04 18.Qh4 Qe8 19.d5 Kg7 20.Rac1 Qa4 21.Ra1
8/22+ 00:00 18k 887k -3.94 18.Qh4 Qe8 19.Rad1 Qd8 20.d5 Re5 21.Nf3+ Kf7
8/22+ 00:00 20k 680k -3.84 18.Qh4 Qe8 19.Rad1 Nc6 20.d5 Qd7
8/28+ 00:00 36k 1,206k -3.64 18.Qh4 Qe8 19.Rad1 Nc6 20.d5 Ke5
8/28 00:00 38k 953k -3.63 18.Qh4 Qe8 19.Rad1 Nc4 20.Rc1 Nb2 21.Rc3 Kg7
9/28 00:00 44k 1,098k -3.59 18.Qh4 Qe8 19.Rad1 Nc4 20.Rc1 Nb2 21.Rc3 Kg7 22.d5
10/28- 00:00 53k 1,066k -3.69 18.Qh4 Qe8 19.Nh7+ Kg7 20.Nf6 Qh8 21.Nh5+ Kf8 22.Rfd1
10/28- 00:00 62k 1,041k -3.79 18.Qh4 Qe8 19.Rad1 a6 20.e5+ dxe5 21.f4 exf4 22.Qxf4+ Kg7 23.Rf3
10/28 00:00 89k 1,115k -3.82 18.Qh4 Qe8 19.Rad1 Nc4 20.Rc1 Nb2 21.Rc3 Kg7 22.Rf3 Kg8
11/28+ 00:00 123k 1,370k -3.72 18.Qh4 Qe8 19.d5 Kg7 20.Qh7+ Kf6 21.Qh4 Qd8
11/28+ 00:00 129k 1,294k -3.62 18.Qh4 Qe8 19.d5 Kg7 20.Qh7+ Kf6 21.Qh4 c5 22.Rac1 Kg7
11/36+ 00:00 185k 1,423k -3.42 18.Qh4 Qe8 19.d5 Kg7 20.Qh7+ Kf6 21.Qh4 Nc4 22.Ne6+ Ke5 23.Qg5+ Kxe4 24.Rad1
11/36 00:00 244k 1,527k -4.07 18.Qh4 Qg8 19.Nh7+ Kf7 20.Qf4+ Kg7 21.Qf6+ Kxh7 22.Qxe7+ Qg7 23.Qh4+ Kg8 24.Qd8+ Kf7 25.d5 Qf6 26.Qxf6+ Kxf6 27.Rac1 Bg4
12/36+ 00:00 252k 1,573k -3.97 18.Qh4 Qg8 19.Nh7+ Kf7 20.Qf4+ Kg7 21.Qf6+ Kxh7 22.Qxe7+ Qg7 23.Qh4+ Kg8 24.Qd8+ Kf7 25.d5 Qf6 26.Qxf6+ Kxf6 27.Rac1 Bd7 28.Rfd1
12/36 00:00 274k 1,610k -3.93 18.Qh4 Qg8 19.Nh7+ Kf7 20.Qf4+ Kg7 21.Qf6+ Kxh7 22.Qxe7+ Qg7 23.Qh4+ Kg8 24.Qd8+ Qf8 25.Qg5 Kg7 26.Rac1 Nc6 27.d5
13/36- 00:00 333k 1,663k -4.03 18.Qh4 Qg8 19.Nh7+ Kf7 20.Qf4+ Kg7 21.Qf6+ Kxh7 22.Qxe7+ Qg7 23.Qh4+ Kg8 24.Qd8+ Qf8 25.Qg5 Kg7 26.Rac1 Nc6 27.Rce1
13/36- 00:00 438k 1,684k -4.13 18.Qh4 Qg8 19.Nh7+ Kf7 20.Qf4+ Kg7 21.Qf6+ Kxh7 22.Qxe7+ Qg7 23.Qh4+ Kg8 24.Qd8+ Qf8 25.Qg5 Kg7 26.Rac1 Nc6 27.Ra1
13/36 00:00 522k 1,740k -4.22 18.Qh4 Qg8 19.Nh7+ Kf7 20.Qf4+ Kg7 21.Qf6+ Kxh7 22.Qxe7+ Qg7 23.Qh4+ Kg8 24.Qd8+ Qf8 25.Qg5 Kg7 26.Rad1 Nc6 27.Qe3 Bg4
14/36 00:00 631k 1,803k -4.23 18.Qh4 Qg8 19.Nh7+ Kf7 20.Qf4+ Kg7 21.Qf6+ Kxh7 22.Qxe7+ Qg7 23.Qh4+ Kg8 24.Qd8+ Qf8 25.Qxf8+ Kxf8 26.d5 Bg4 27.Rfe1 Ke7 28.h3 Rf8 29.hxg4 Bxf2+ 30.Kf1 Bxe1+
15/36 00:00 886k 1,910k -4.27 18.Qh4 Qg8 19.Nh7+ Kf7 20.Qf4+ Kg7 21.Qf6+ Kxh7 22.Qxe7+ Qg7 23.Qh4+ Kg8 24.Qd8+ Qf8 25.Qg5 Kg7 26.d5 Nc4 27.Rac1 Ne5 28.Qd2 Qf6
16/36+ 00:00 1,040k 1,911k -4.17 18.Qh4 Qg8 19.Nh7+ Kf7 20.Qf4+ Kg7 21.Qf6+ Kxh7 22.Qxe7+ Qg7 23.Qh4+ Kg8 24.Qd8+ Qf8 25.Qg5 Kg7 26.Qd2 Nc4 27.Qc3 Qf7 28.Rfc1 a5
16/36 00:00 1,292k 1,975k -4.10 18.Qh4 Qg8 19.Nh7+ Kf7 20.Qf4+ Kg7 21.Qf6+ Kxh7 22.Qxe7+ Qg7 23.Qh4+ Kg8 24.Qd8+ Qf8 25.Qg5 Kg7 26.Qd2 Qf6 27.Rac1 Nc6 28.d5 Ne5 29.h3
17/36- 00:00 1,891k 2,069k -4.20 18.Qh4 Qg8 19.Nh7+ Kf7 20.Qf4+ Kg7 21.Qf6+ Kxh7 22.Qxe7+ Qg7 23.Qh4+ Kg8 24.Qd8+ Qf8 25.Qg5 Kg7 26.Qd2 Qf6 27.Rac1 Nc6 28.d5 Ne5 29.Rfd1
17/36- 00:01 2,536k 2,142k -4.30 18.Qh4 Qg8 19.Nh7+ Kf7 20.Qf4+ Kg7 21.Qf6+ Kxh7 22.Qxe7+ Qg7 23.Qh4+ Kg8 24.Qd8+ Qf8 25.Qg5 Kg7 26.Qd2 Qf6 27.Rac1 Nc6 28.d5 Ne5 29.Qc3
17/36 00:01 3,809k 2,217k -4.49 18.Qh4 Qg8 19.Nh7+ Kf7 20.Qf4+ Kg7 21.Qf6+ Kxh7 22.Qxe7+ Qg7 23.Qh4+ Kg8 24.Qd8+ Qf8 25.Qg5 Kg7 26.h4 Qf6 27.Qxf6+ Kxf6 28.d5 Ke5 29.Rfe1 Bd7 30.Rac1 Rf8
18/36 00:02 5,132k 2,261k -4.51 18.Qh4 Qg8 19.Nh7+ Kf7 20.Qf4+ Kg7 21.Qf6+ Kxh7 22.Qxe7+ Qg7 23.Qh4+ Kg8 24.Qd8+ Qf8 25.Qg5 Kg7 26.Rad1 Nc6 27.d5 Ne5 28.Qd2 Qf6 29.Rc1 Bd7 30.h3
19/41- 00:03 9,036k 2,346k -4.61 18.Qh4 Qg8 19.Nh7+ Kf7 20.Qf4+ Kg7 21.Qf6+ Kxh7 22.Qxe7+ Qg7 23.Qh4+ Kg8 24.Qd8+ Qf8 25.Qg5 Kg7 26.Rad1 Nc6 27.d5 Ne5 28.Qd2 Qf6 29.Rc1 Bd7 30.Rc2
19/41 00:04 10,877k 2,374k -4.57 18.Qh4 Qg8 19.Nh7+ Kf7 20.Qf4+ Kg7 21.Qf6+ Kxh7 22.Qxe7+ Qg7 23.Qh4+ Kg8 24.Qd8+ Qf8 25.Qg5 Kg7 26.d5 Bd7 27.h4 Qf6 28.Rac1 Qxg5 29.hxg5 Bb5 30.Rfd1 Rh8 31.g3
20/42 00:06 14,779k 2,387k -4.64 18.Qh4 Qg8 19.Nh7+ Kf7 20.Qf4+ Kg7 21.Qf6+ Kxh7 22.Qxe7+ Qg7 23.Qh4+ Kg8 24.Qd8+ Qf8 25.Qg5 Kg7 26.h4 Qf6 27.Qxf6+ Kxf6 28.Rac1 Nc6 29.d5 Ne5 30.Rc3 Bd7 31.Rfc1 Rf8 32.a3
21/42 00:10 25,088k 2,426k -4.67 18.Qh4 Qg8 19.Nh7+ Kf7 20.Qf4+ Kg7 21.Qf6+ Kxh7 22.Qxe7+ Qg7 23.Qh4+ Kg8 24.Qd8+ Qf8 25.Qg5 Kg7 26.h4 Qf6 27.Rac1 Nc6 28.d5 Ne5 29.Qxf6+ Kxf6 30.Kh2 Bd7 31.f4 Ng4+ 32.Kg3 Rh8 33.Rc4
22/42- 00:15 38,490k 2,468k -4.77 18.Qh4 Qg8 19.Nh7+ Kf7 20.Qf4+ Kg7 21.Qf6+ Kxh7 22.Qxe7+ Qg7 23.Qh4+ Kg8 24.Qd8+ Qf8 25.Qg5 Kg7 26.h4 Qf6 27.Rac1 Nc6 28.d5 Ne5 29.Qxf6+ Kxf6 30.Kh2 Bd7 31.a3 Nd3 32.Rb1
22/45 00:25 63,363k 2,526k -4.82 18.Qh4 Qg8 19.Nh7+ Kf7 20.Qf4+ Kg7 21.Qf6+ Kxh7 22.Qxe7+ Qg7 23.Qh4+ Kg8 24.Qd8+ Qf8 25.Qg5 Kg7 26.h4 Qf6 27.Rac1 Nc6 28.d5 Ne5 29.Qxf6+ Kxf6 30.Rc3 Bg4 31.Rfc1 Rh8 32.g3 c5 33.f4
23/47 00:39 99,155k 2,516k -4.91 18.Qh4 Qg8 19.Nh7+ Kf7 20.Qf4+ Kg7 21.Qf6+ Kxh7 22.Qxe7+ Qg7 23.Qh4+ Kg8 24.Qd8+ Qf8 25.Qg5 Kg7 26.h4 Qf6 27.Rac1 Qxg5 28.hxg5 Bd7 29.Rfd1 Rf8 30.Rd2 Nc6 31.Rc4 Rf4 32.f3 Be6 33.Ra4
23/52+ 01:31 233,707k 2,551k -4.72 18.Qh6 Bxd4 19.Rad1 Nc6 20.Rd3 Bg4 21.Nf3 Rxe4 22.Nxd4 Nxd4 23.f3 Ne2+ 24.Kf2 Nf4 25.fxe4 Nxd3+ 26.Kg1+ Ke7 27.Qg5+ Ke8 28.Qxg4 Ke7
23/52 01:44 268,137k 2,555k -4.88 18.Qh6 Bxd4 19.Rad1 Nc6 20.Rd3 Bg4 21.Nf3 Rxe4 22.Nxd4 Nxd4 23.f3 Ne2+ 24.Kh1 Rf4 25.Re3 Qh8 26.Qxh8+ Rxh8 27.Rxe2 Bd7 28.Rfe1 c5 29.Kg1 Kg5 30.Re7 Bc6 31.h3 c4 32.Kf2 c3 33.R1e2
23/52+ 01:57 302,797k 2,571k -4.62 18.e5+ Kxg5 19.f4+ Kf5 20.Qh3+ Ke4 21.Qf3+ Kxd4 22.Rac1 Nc4 23.Rfd1+ Kc5 24.Qd5+ Kb4+ 25.Kh1 Be6 26.Rxc4+ Ka3 27.Qd3+ Kxa2
23/52+ 02:00 310,832k 2,573k -4.42 18.e5+ Kxg5 19.f4+ Kf5 20.Qh3+ Ke4 21.Qf3+ Kxd4 22.Rac1 Nc4 23.Rfd1+ Kc5 24.Qd5+ Kb4+ 25.Kh1 Ne3 26.Rb1+ Kc3 27.Qb5 Bd4
23/55+ 02:10 337,654k 2,581k -4.02 18.e5+ Kxg5 19.f4+ Kf5 20.Qh3+ Ke4 21.Qf3+ Kxd4 22.Rac1 Nc4 23.Rfd1+ Kc5 24.Qd5+ Kb4+ 25.Kh1 Ne3 26.Rb1+ Kc3 27.Qb5 dxe5 28.Rxd8 Bg4
23/55+ 02:19 363,026k 2,596k -3.22 18.e5+ Kxg5 19.f4+ Kf5 20.Qh3+ Ke4 21.Qf3+ Kxd4 22.Rac1 Nc4 23.Rfd1+ Kc5 24.Qd5+ Kb4+ 25.Kh1 Ne3 26.Rb1+ Kc3 27.Qb5 Bd4 28.exd6 Re4
23/55+ 02:36 412,358k 2,632k -1.62 18.e5+ Kxg5 19.f4+ Kf5 20.Qh3+ Ke4 21.Qf3+ Kxd4 22.Rac1 Nc4 23.Rfd1+ Kc5 24.Qd5+ Kb4+ 25.Kh1 Ne3 26.Rb1+ Kc3 27.Qb5 Be6 28.Rbc1+ Nc2 29.exd6 Bc4 30.Rxc2+ Kxc2 31.Qa4+ Kc3 32.dxe7 Qxd1+ 33.Qxd1 Be3

[Lyudmil Tsvetkov]

I don't get it, why this is so hard for Stockfish. If in check there is no early pruning, so that should rule out nullmove, ProbCut, Futility pruning when above alpha (or the so called static static eval makes no difference. Modifying LMR makes no difference. nullmove). In the next ply any check then receives an extension of a full ply, unless the check has a negative Static Exchange Evaluation. Modifying the extension rule to include all checks when in positions with a with a bad

This position takes too long:

[pgn]
[Event "?"]
[Site "?"]
[Date "2014.12.13"]
[Round "?"]
[White "?"]
[Black "?"]
[Result "*"]

1. e4 e5 2. Nf3 Nc6 3. Bc4 Bc5 4. b4 Bxb4 5. c3 Bc5 6. d4
exd4 7. O-O d6 8. cxd4 Bb6 9. Nc3 Na5 10. Bg5 Ne7 11. Bxf7+
Kxf7 12. Nd5 Re8 13. Bxe7 Rxe7 14. Ng5+ Kg8 15. Qh5 g6 *[/pgn]


[d]r1bq2k1/ppp1r2p/1b1p2p1/n2N2NQ/3PP3/8/P4PPP/R4RK1 w - -

Engine: Sf20141112_007 MOD MP (Q6700, 4 threads, 512 MB)
by Tord Romstad, Marco Costalba and Joona Kiiski

18/22 0:01 -2.12 16.Qh4 Rf7 17.Qh6 Rg7 18.e5 dxe5
19.Nxh7 Rxh7 20.Qxg6+ Rg7 21.Nf6+ Kf8
22.Qh6 Qd6 23.dxe5 Qc6 24.g3 Nc4
25.Qh8+ Kf7 26.Nh5 (2.843.737) 2346

19/24 0:02 -3.00 16.Qh4 Rf7 17.Rfd1 c6 18.Nxb6 axb6
19.Rdc1 b5 20.Qh6 Re7 21.Rc3 d5
22.Rg3 Qf8 23.Qxf8+ Kxf8 24.exd5 Nc4
25.dxc6 bxc6 (5.475.036) 2470

20/25 0:02 -2.92 16.Qh6 Rg7 17.e5 dxe5 18.Nxh7 Rxh7
19.Qxg6+ Rg7 20.Nf6+ Kf8 21.Qh6 Qd6
22.dxe5 Qxe5 23.Rae1 Bxf2+ 24.Kxf2 Qc5+
25.Qe3 Qxe3+ 26.Kxe3 Rxg2 27.Nd5+ Kg8
28.Nxc7 Nc4+ 29.Kd3 (7.111.630) 2521

21/27 0:03 -2.70++ 16.Qh6 (7.615.214) 2533

21/27 0:03 -2.56++ 16.Qh6 (7.748.248) 2537

21/27 0:03 -2.36++ 16.Qh6 (7.937.124) 2540

21/28 0:03 -2.19 16.Qh6 Qf8 17.Qxf8+ Kxf8 18.Nxe7 Kxe7
19.d5 h6 20.Nf3 Bd7 21.Rab1 g5 22.h3 Rf8
23.Nd2 c6 24.Rbc1 Bc5 25.Rb1 a6
26.dxc6 (9.594.539) 2547

22/28 0:04 -2.27-- 16.Qh6 Qf8 (10.484.648) 2575

22/28 0:04 -2.20++ 16.Qh6 (10.938.725) 2587

22/28 0:04 -2.27-- 16.Qh6 Qf8 (11.186.888) 2586

22/28 0:04 -2.22 16.Qh6 Qf8 17.Qxf8+ Kxf8 18.Nxe7 Kxe7
19.d5 h6 20.Nf3 Bg4 21.Rac1 g5 22.h4 Bxf3
23.gxf3 gxh4 24.Kg2 c6 25.dxc6 Nxc6
26.f4 Nb4 27.Rcd1 Nxa2 (11.431.607) 2574

23/28 0:05 -2.22 16.Qh6 Qf8 17.Qxf8+ Kxf8 18.Nxe7 Kxe7
19.d5 h6 20.Nf3 Bd7 21.Rfc1 Rf8
22.Rc3 g5 23.h3 h5 24.Rf1 g4 25.Nh4 Rf6
26.hxg4 hxg4 27.Rcc1 g3 (14.926.409) 2577

24/28 0:07 -2.31-- 16.Qh6 Qf8 (18.466.728) 2630

24/31 0:07 -2.37-- 16.Qh6 Qf8 (20.057.161) 2653

24/31 0:08 -2.46-- 16.Qh6 Rg7 (23.026.163) 2674

24/31 0:08 -2.38++ 16.Qh6 (23.802.583) 2673

24/31 0:09 -2.49-- 16.Qh6 Rg7 (24.640.538) 2680

24/31 0:09 -2.60 16.Qh6 Rg7 17.e5 dxe5 18.Nxh7 Bxd4
19.Ndf6+ Kf7 20.Rac1 Nc6 21.Rfd1 Bf5
22.g4 Be6 23.a3 Qh8 24.Re1 Bxg4
25.Rb1 Rxh7 26.Nxh7 Qg7 27.Ng5+ Kg8
28.Qxg7+ Kxg7 29.Rxb7 (26.792.204) 2680

25/31 0:11 -2.70-- 16.Qh6 Rg7 (29.868.002) 2695

25/31 0:12 -2.76-- 16.Qh6 Rg7 (33.015.009) 2701

25/31 0:13 -2.69++ 16.Qh6 (35.549.673) 2707

25/31 0:14 -2.77-- 16.Qh6 Rg7 (38.329.191) 2714

25/31 0:14 -2.66++ 16.Qh6 (40.141.489) 2710

25/32 0:15 -2.82-- 16.Qh6 Rg7 (43.166.321) 2711

25/32 0:16 -2.58++ 16.Qh6 (43.812.114) 2708

25/32 0:16 -2.53 16.Qh6 Rg7 17.e5 dxe5 18.Nxh7 Rxh7
19.Qxg6+ Rg7 20.Nf6+ Kf8 21.Qh6 Nc6
22.dxe5 Bd4 23.Rad1 Be6 24.Rfe1 Qe7
25.Qf4 a5 26.Rxd4 Nxd4 27.Nh7+ Ke8
28.Nf6+ Kd8 29.Qxd4+ (44.664.436) 2706

26/32 0:18 -2.63-- 16.Qh6 Rg7 (50.509.486) 2723

26/32 0:19 -2.69-- 16.Qh6 Rg7 (52.278.063) 2729

26/32 0:20 -2.78-- 16.Qh6 Rg7 (55.809.111) 2727

26/33 0:23 -2.92-- 16.Qh6 Rg7 (63.343.433) 2732

26/34 0:27 -2.82 16.Qh6 Rg7 17.e5 dxe5 18.Nxh7 Bxd4
19.Ndf6+ Kf7 20.Rfd1 Nc4 21.Rab1 Bf5
22.Rbc1 Nb2 23.Rd2 (74.624.476) 2734

27/34 0:30 -2.93-- 16.Qh6 Rg7 (82.795.044) 2744

27/34 0:32 -2.99-- 16.Qh6 Rg7 (90.342.500) 2754

27/34 0:33 -2.92++ 16.Qh6 (91.910.793) 2749

27/34 0:33 -2.78++ 16.Qh6 (92.959.136) 2750

27/34 0:34 -2.72 16.Qh6 Rg7 17.e5 dxe5 18.Nxh7 Rxh7
19.Qxg6+ Rg7 20.Nf6+ Kf8 21.Qh6 Nc6
22.dxe5 Bd4 23.Rad1 Be6 24.Rfe1 Nxe5
25.Qf4 Rf7 26.Nh7+ Kg8 27.Qxd4 Qxd4
28.Rxd4 Rf5 29.Nf6+ (95.234.996) 2746

28/35 0:35 -2.66++ 16.Qh6 (98.126.808) 2737

28/35 0:36 -2.60++ 16.Qh6 (99.003.482) 2737

28/35 0:39 -2.67-- 16.Qh6 Rg7 (108.944.952) 2743

28/35 0:42 -2.81-- 16.Qh6 Rg7 (116.148.109) 2744

28/36 0:51 -3.02-- 16.Qh6 Rg7 (139.689.516) 2734

28/36 0:56 -3.04 16.Qh6 Rg7 17.e5 dxe5 18.Nxh7 Rxh7
19.Qxg6+ Rg7 20.Nf6+ Kf8 21.Qh6 Bh3
22.Nh5 Qg5 23.Qxg7+ Qxg7 24.Nxg7 Kxg7
25.gxh3 exd4 26.Rac1 c5 27.Rfe1 c4
28.Kg2 Rh8 29.Re6 (153.406.944) 2732

29/36 0:57 -2.98++ 16.Qh6 (158.455.092) 2737

29/36 1:02 -2.92++ 16.Nf6+ (170.541.947) 2747

29/36 1:03 -2.82++ 16.Nf6+ (172.961.030) 2743

29/36 1:03 -2.68++ 16.Nf6+ (174.445.152) 2741

29/36 1:04 -2.48++ 16.Nf6+ (177.849.209) 2741

29/36 1:05 -2.16++ 16.Nf6+ (180.781.854) 2742

29/44 1:06 -1.69++ 16.Nf6+ (181.882.047) 2742

29/44 1:07 -0.99++ 16.Nf6+ (184.537.294) 2744

29/46 1:09 0.00 16.Nf6+ Kg7 17.Qxh7+ Kxf6 18.e5+ Kxg5
19.f4+ Kf5 20.Qh3+ Ke4 21.Qf3+ Kf5
22.Qh3+ (190.793.941) 2744

30/46 1:12 0.00 16.Nf6+ Kg7 17.Qxh7+ Kxf6 18.e5+ Kxg5
19.f4+ Kf5 20.Qh3+ Ke4 21.Qf3+ Kf5
22.Qh3+ (198.123.578) 2738

31/46 1:14 0.00 16.Nf6+ Kg7 17.Qxh7+ Kxf6 18.e5+ Kxg5
19.f4+ Kf5 20.Qh3+ Ke4 21.Qf3+ Kf5
22.Qh3+ (203.612.249) 2739

32/46 1:18 0.00 16.Nf6+ Kg7 17.Qxh7+ Kxf6 18.e5+ Kxg5
19.f4+ Kf5 20.Qh3+ Ke4 21.Qf3+ Kf5
22.Qh3+ (215.338.585) 2739

33/46 1:24 0.00 16.Nf6+ Kg7 17.Qxh7+ Kxf6 18.e5+ Kxg5
19.f4+ Kf5 20.Qh3+ Ke4 21.Qf3+ Kf5
22.Qh3+ (231.371.189) 2742

34/46 1:33 0.00 16.Nf6+ Kg7 17.Qxh7+ Kxf6 18.e5+ Kxg5
19.f4+ Kf5 20.Qh3+ Ke4 21.Qf3+ Kf5
22.Qh3+ (256.895.682) 2753

35/46 1:41 0.00 16.Nf6+ Kg7 17.Qxh7+ Kxf6 18.e5+ Kxg5
19.f4+ Kf5 20.Qh3+ Ke4 21.Qf3+ Kf5
22.Qh3+ (279.085.410) 2746

36/46 2:00 0.00 16.Nf6+ Kg7 17.Qxh7+ Kxf6 18.e5+ Kxg5
19.f4+ Kf5 20.Qh3+ Ke4 21.Qf3+ Kf5
22.Qh3+ (334.526.088) 2779

37/46 2:22 0.00 16.Nf6+ Kg7 17.Qxh7+ Kxf6 18.e5+ Kxg5
19.f4+ Kf5 20.Qh3+ Ke4 21.Qf3+ Kf5
22.Qh3+ (399.966.144) 2804

38/46 2:38 0.00 16.Nf6+ Kg7 17.Qxh7+ Kxf6 18.e5+ Kxg5
19.f4+ Kf5 20.Qh3+ Ke4 21.Qf3+ Kf5
22.Qh3+ (445.742.035) 2808

39/46 3:01 0.00 16.Nf6+ Kg7 17.Qxh7+ Kxf6 18.e5+ Kxg5
19.f4+ Kf5 20.Qh3+ Ke4 21.Qf3+ Kf5
22.Qh3+ (515.031.273) 2830

40/46 3:50 0.00 16.Nf6+ Kg7 17.Qxh7+ Kxf6 18.e5+ Kxg5
19.f4+ Kf5 20.Qh3+ Ke4 21.Qf3+ Kf5
22.Qh3+ (665.189.582) 2883

best move: Nd5-f6 time: 4:18.666 min n/s: 2.883.728 nodes: 748.052.485

Too low king psqt mg penalty?

SF seems to penalise d8/e8 squares 4 times more than d4/e4/d5/e5 squares, but if this is the right approach is not at all clear; I would say rather not, because on d8/e8 mate is easily seen, but might be somewhat problematic in the center.

I think all c3-f3-f6-c6 squares within the rectangle should be penalised higher.

Playing with a significant material disadvantage when the position requires it is one of the most notable engine weaknesses. Engines like to see lines where material gets recuperated quickly, but some lines simply require recuperating it much later.

[Eelco de Groot]

I think Uri is on the right track the engines think that the king can walk out of the checks by capturing Ke4xd4

Stockfish 101214 by Tord Romstad, Marco Costalba and Joona Kiiski
position fen [d]r1bq4/ppp1r2Q/1b1p1kp1/n3P1N1/3P4/8/P4PPP/R4RK1 b - -
go depth 20
info depth 1 seldepth 1 multipv 1 score cp 471 nodes 130 nps 43333 tbhits 0 time
3 pv f6g5 f2f4 g5f5
info depth 2 seldepth 3 multipv 1 score cp 422 nodes 250 nps 62500 tbhits 0 time
4 pv f6g5 f2f4 g5f5 h7h3 f5e4
info depth 3 seldepth 5 multipv 1 score cp 422 nodes 392 nps 78400 tbhits 0 time
5 pv f6g5 f2f4 g5f5 h7h3 f5e4
info depth 4 seldepth 7 multipv 1 score cp 455 nodes 1120 nps 160000 tbhits 0 ti
me 7 pv f6g5 f2f4 g5f5 h7h3 f5e4 h3f3 e4d4
info depth 5 seldepth 10 multipv 1 score cp 480 nodes 2234 nps 248222 tbhits 0 t
ime 9 pv f6g5 f2f4 g5f5 h7h3 f5e4 h3f3 e4d4 a1d1 d4c4 g1h1
info depth 6 seldepth 11 multipv 1 score cp 421 nodes 4019 nps 287071 tbhits 0 t
ime 14 pv f6g5 f2f4 g5f5 h7h3 f5e4 h3f3 e4d4 a1c1 a5c4 f1d1 d4c5
info depth 7 seldepth 11 multipv 1 score cp 421 nodes 5060 nps 297647 tbhits 0 t
ime 17 pv f6g5 f2f4 g5f5 h7h3 f5e4 h3f3 e4d4 a1c1 a5c4 f1d1 d4c5
info depth 8 seldepth 12 multipv 1 score cp 442 nodes 9073 nps 362920 tbhits 0 t
ime 25 pv f6g5 f2f4 g5f5 h7h3 f5e4 h3f3 e4d4 a1c1 a5c4 e5d6 c7d6
info depth 9 seldepth 20 multipv 1 score cp 448 nodes 37547 nps 475278 tbhits 0
time 79 pv f6g5 f2f4 g5f5 h7h3 f5e4 h3f3 e4d4 a1c1 a5c4 f1d1 d4c5 f3d5 c5b4 g1h1
c4a5 c1b1 b4a3
info depth 10 seldepth 23 multipv 1 score cp 437 nodes 39567 nps 476710 tbhits 0
time 83 pv f6g5 f2f4 g5f5 h7h3 f5e4 h3f3 e4d4 a1c1 a5c4 f1d1 d4c5 f3d5 c5b4 g1h
1 c4a5 c1b1 b4a3
info depth 11 seldepth 24 multipv 1 score cp 201 nodes 52511 nps 477372 tbhits 0
time 110 pv f6g5 f2f4 g5f5 h7h3 f5e4 h3f3 e4d4 a1c1 a5c4 f1d1 d4c5 f3d5 c5b4 g1
h1 c4b2 d5b3 b4a5 b3b2
info depth 12 seldepth 24 multipv 1 score cp 194 nodes 61703 nps 478317 tbhits 0
time 129 pv f6g5 f2f4 g5f5 h7h3 f5e4 h3f3 e4d4 a1c1 a5c4 f1d1 d4c5 f3d5 c5b4 g1
h1 c4b2 d5b3 b4a5 b3b2 c8g4 e5d6
info depth 13 seldepth 29 multipv 1 score cp 128 nodes 111718 nps 553059 tbhits
0 time 202 pv f6g5 f2f4 g5f5 h7h3 f5e4 h3f3 e4d4 a1c1 a5c4 f1d1 d4c5 f3d5 c5b4 g
1h1 c4b2 d5b3 b4a5 d1d5 c7c5 b3b2 e7e6 c1b1
info depth 14 seldepth 33 multipv 1 score cp 0 nodes 255759 nps 666039 tbhits 0
time 384 pv f6g5 f2f4 g5f5 h7h3 f5e4 h3f3 e4d4 a1c1 a5c4 f1d1 d4c5 f3d5 c5b4 g1h
1 c4b2 c1b1 d8e8 b1b2 b4a4 d5b3 a4a5 b3c3 a5a6 c3d3 a6a5 d3c3
info depth 15 seldepth 33 multipv 1 score cp 0 nodes 348977 nps 700757 tbhits 0
time 498 pv f6g5 f2f4 g5f5 h7h3 f5e4 h3f3 e4d4 a1c1 a5c4 f1d1 d4c5 f3d5 c5b4 g1h
1 c4b2 c1b1 d8e8 b1b2 b4a4 d5b3 a4a5 b3c3 a5a6 c3d3 a6a5 d3c3
info depth 16 seldepth 35 multipv 1 score cp 0 nodes 420989 nps 723348 tbhits 0
time 582 pv f6g5 f2f4 g5f5 h7h3 f5e4 h3f3 e4f5 f3h3
info depth 17 seldepth 35 multipv 1 score cp 0 nodes 474936 nps 734058 tbhits 0
time 647 pv f6g5 f2f4 g5f5 h7h3 f5e4 h3f3 e4f5 f3h3
info depth 18 seldepth 35 multipv 1 score cp 0 nodes 541657 nps 745057 tbhits 0
time 727 pv f6g5 f2f4 g5f5 h7h3 f5e4 h3f3 e4f5 f3h3
info depth 19 seldepth 35 multipv 1 score cp 0 nodes 618270 nps 756756 tbhits 0
time 817 pv f6g5 f2f4 g5f5 h7h3 f5e4 h3f3 e4f5 f3h3
info depth 20 seldepth 35 multipv 1 score cp 0 nodes 728176 nps 771372 tbhits 0
time 944 pv f6g5 f2f4 g5f5 h7h3 f5e4 h3f3 e4f5 f3h3
bestmove f6g5 ponder f2f4


18. e5+ Kxg5 19. f4+ Kf5 20. Qh3+ Ke4 21. Qf3+ Kxd4 *

After 21... Kxd4 comes a quiet move 22. Rac1!, that is the hard one to find apparently. So the good news is, it is not a bug with check extensions but once again a quiet move. Stockfish sees the move a1c1 as early as depth 6! but not how good that move is...

[d]r1bq4/ppp1r3/1b1p2p1/n3P3/3k1P2/5Q2/P5PP/R4RK1 w - -

[Lyudmil Tsvetkov]

I think Uri is on the right track the engines think that the king can walk out of the checks by capturing Ke4xd4

Stockfish 101214 by Tord Romstad, Marco Costalba and Joona Kiiski
position fen [d]r1bq4/ppp1r2Q/1b1p1kp1/n3P1N1/3P4/8/P4PPP/R4RK1 b - -
go depth 20
info depth 1 seldepth 1 multipv 1 score cp 471 nodes 130 nps 43333 tbhits 0 time
3 pv f6g5 f2f4 g5f5
info depth 2 seldepth 3 multipv 1 score cp 422 nodes 250 nps 62500 tbhits 0 time
4 pv f6g5 f2f4 g5f5 h7h3 f5e4
info depth 3 seldepth 5 multipv 1 score cp 422 nodes 392 nps 78400 tbhits 0 time
5 pv f6g5 f2f4 g5f5 h7h3 f5e4
info depth 4 seldepth 7 multipv 1 score cp 455 nodes 1120 nps 160000 tbhits 0 ti
me 7 pv f6g5 f2f4 g5f5 h7h3 f5e4 h3f3 e4d4
info depth 5 seldepth 10 multipv 1 score cp 480 nodes 2234 nps 248222 tbhits 0 t
ime 9 pv f6g5 f2f4 g5f5 h7h3 f5e4 h3f3 e4d4 a1d1 d4c4 g1h1
info depth 6 seldepth 11 multipv 1 score cp 421 nodes 4019 nps 287071 tbhits 0 t
ime 14 pv f6g5 f2f4 g5f5 h7h3 f5e4 h3f3 e4d4 a1c1 a5c4 f1d1 d4c5
info depth 7 seldepth 11 multipv 1 score cp 421 nodes 5060 nps 297647 tbhits 0 t
ime 17 pv f6g5 f2f4 g5f5 h7h3 f5e4 h3f3 e4d4 a1c1 a5c4 f1d1 d4c5
info depth 8 seldepth 12 multipv 1 score cp 442 nodes 9073 nps 362920 tbhits 0 t
ime 25 pv f6g5 f2f4 g5f5 h7h3 f5e4 h3f3 e4d4 a1c1 a5c4 e5d6 c7d6
info depth 9 seldepth 20 multipv 1 score cp 448 nodes 37547 nps 475278 tbhits 0
time 79 pv f6g5 f2f4 g5f5 h7h3 f5e4 h3f3 e4d4 a1c1 a5c4 f1d1 d4c5 f3d5 c5b4 g1h1
c4a5 c1b1 b4a3
info depth 10 seldepth 23 multipv 1 score cp 437 nodes 39567 nps 476710 tbhits 0
time 83 pv f6g5 f2f4 g5f5 h7h3 f5e4 h3f3 e4d4 a1c1 a5c4 f1d1 d4c5 f3d5 c5b4 g1h
1 c4a5 c1b1 b4a3
info depth 11 seldepth 24 multipv 1 score cp 201 nodes 52511 nps 477372 tbhits 0
time 110 pv f6g5 f2f4 g5f5 h7h3 f5e4 h3f3 e4d4 a1c1 a5c4 f1d1 d4c5 f3d5 c5b4 g1
h1 c4b2 d5b3 b4a5 b3b2
info depth 12 seldepth 24 multipv 1 score cp 194 nodes 61703 nps 478317 tbhits 0
time 129 pv f6g5 f2f4 g5f5 h7h3 f5e4 h3f3 e4d4 a1c1 a5c4 f1d1 d4c5 f3d5 c5b4 g1
h1 c4b2 d5b3 b4a5 b3b2 c8g4 e5d6
info depth 13 seldepth 29 multipv 1 score cp 128 nodes 111718 nps 553059 tbhits
0 time 202 pv f6g5 f2f4 g5f5 h7h3 f5e4 h3f3 e4d4 a1c1 a5c4 f1d1 d4c5 f3d5 c5b4 g
1h1 c4b2 d5b3 b4a5 d1d5 c7c5 b3b2 e7e6 c1b1
info depth 14 seldepth 33 multipv 1 score cp 0 nodes 255759 nps 666039 tbhits 0
time 384 pv f6g5 f2f4 g5f5 h7h3 f5e4 h3f3 e4d4 a1c1 a5c4 f1d1 d4c5 f3d5 c5b4 g1h
1 c4b2 c1b1 d8e8 b1b2 b4a4 d5b3 a4a5 b3c3 a5a6 c3d3 a6a5 d3c3
info depth 15 seldepth 33 multipv 1 score cp 0 nodes 348977 nps 700757 tbhits 0
time 498 pv f6g5 f2f4 g5f5 h7h3 f5e4 h3f3 e4d4 a1c1 a5c4 f1d1 d4c5 f3d5 c5b4 g1h
1 c4b2 c1b1 d8e8 b1b2 b4a4 d5b3 a4a5 b3c3 a5a6 c3d3 a6a5 d3c3
info depth 16 seldepth 35 multipv 1 score cp 0 nodes 420989 nps 723348 tbhits 0
time 582 pv f6g5 f2f4 g5f5 h7h3 f5e4 h3f3 e4f5 f3h3
info depth 17 seldepth 35 multipv 1 score cp 0 nodes 474936 nps 734058 tbhits 0
time 647 pv f6g5 f2f4 g5f5 h7h3 f5e4 h3f3 e4f5 f3h3
info depth 18 seldepth 35 multipv 1 score cp 0 nodes 541657 nps 745057 tbhits 0
time 727 pv f6g5 f2f4 g5f5 h7h3 f5e4 h3f3 e4f5 f3h3
info depth 19 seldepth 35 multipv 1 score cp 0 nodes 618270 nps 756756 tbhits 0
time 817 pv f6g5 f2f4 g5f5 h7h3 f5e4 h3f3 e4f5 f3h3
info depth 20 seldepth 35 multipv 1 score cp 0 nodes 728176 nps 771372 tbhits 0
time 944 pv f6g5 f2f4 g5f5 h7h3 f5e4 h3f3 e4f5 f3h3
bestmove f6g5 ponder f2f4


18. e5+ Kxg5 19. f4+ Kf5 20. Qh3+ Ke4 21. Qf3+ Kxd4 *

After 21... Kxd4 comes a quiet move 22. Rac1!, that is the hard one to find apparently. So the good news is, it is not a bug with check extensions but once again a quiet move. Stockfish sees the move a1c1 as early as depth 6! but not how good that move is...

[d]r1bq4/ppp1r3/1b1p2p1/n3P3/3k1P2/5Q2/P5PP/R4RK1 w - -

I did not consider the position at all, but I do not believe Rac1 is the only move winning here.
I guess some checks or Kh1 also win.

Look again at the penalty for the black king on d4: not much bigger than for a king on g7, and much lower than for a king on d1. But the location of the king on d4 means almost certain death.

[Joerg Oster]

I don't get it, why this is so hard for Stockfish. If in check there is no early pruning, so that should rule out nullmove, ProbCut, Futility pruning when above alpha (or the so called static nullmove). In the next ply any check then receives an extension of a full ply, unless the check has a negative Static Exchange Evaluation. Modifying the extension rule to include all checks when in positions with a with a bad static eval makes no difference. Modifying LMR makes no difference.

This position takes too long:

[pgn]
[Event "?"]
[Site "?"]
[Date "2014.12.13"]
[Round "?"]
[White "?"]
[Black "?"]
[Result "*"]

1. e4 e5 2. Nf3 Nc6 3. Bc4 Bc5 4. b4 Bxb4 5. c3 Bc5 6. d4
exd4 7. O-O d6 8. cxd4 Bb6 9. Nc3 Na5 10. Bg5 Ne7 11. Bxf7+
Kxf7 12. Nd5 Re8 13. Bxe7 Rxe7 14. Ng5+ Kg8 15. Qh5 g6 *[/pgn]


[d]r1bq2k1/ppp1r2p/1b1p2p1/n2N2NQ/3PP3/8/P4PPP/R4RK1 w - -

Engine: Sf20141112_007 MOD MP (Q6700, 4 threads, 512 MB)
by Tord Romstad, Marco Costalba and Joona Kiiski

18/22 0:01 -2.12 16.Qh4 Rf7 17.Qh6 Rg7 18.e5 dxe5
19.Nxh7 Rxh7 20.Qxg6+ Rg7 21.Nf6+ Kf8
22.Qh6 Qd6 23.dxe5 Qc6 24.g3 Nc4
25.Qh8+ Kf7 26.Nh5 (2.843.737) 2346

19/24 0:02 -3.00 16.Qh4 Rf7 17.Rfd1 c6 18.Nxb6 axb6
19.Rdc1 b5 20.Qh6 Re7 21.Rc3 d5
22.Rg3 Qf8 23.Qxf8+ Kxf8 24.exd5 Nc4
25.dxc6 bxc6 (5.475.036) 2470

20/25 0:02 -2.92 16.Qh6 Rg7 17.e5 dxe5 18.Nxh7 Rxh7
19.Qxg6+ Rg7 20.Nf6+ Kf8 21.Qh6 Qd6
22.dxe5 Qxe5 23.Rae1 Bxf2+ 24.Kxf2 Qc5+
25.Qe3 Qxe3+ 26.Kxe3 Rxg2 27.Nd5+ Kg8
28.Nxc7 Nc4+ 29.Kd3 (7.111.630) 2521

21/27 0:03 -2.70++ 16.Qh6 (7.615.214) 2533

21/27 0:03 -2.56++ 16.Qh6 (7.748.248) 2537

21/27 0:03 -2.36++ 16.Qh6 (7.937.124) 2540

21/28 0:03 -2.19 16.Qh6 Qf8 17.Qxf8+ Kxf8 18.Nxe7 Kxe7
19.d5 h6 20.Nf3 Bd7 21.Rab1 g5 22.h3 Rf8
23.Nd2 c6 24.Rbc1 Bc5 25.Rb1 a6
26.dxc6 (9.594.539) 2547

22/28 0:04 -2.27-- 16.Qh6 Qf8 (10.484.648) 2575

22/28 0:04 -2.20++ 16.Qh6 (10.938.725) 2587

22/28 0:04 -2.27-- 16.Qh6 Qf8 (11.186.888) 2586

22/28 0:04 -2.22 16.Qh6 Qf8 17.Qxf8+ Kxf8 18.Nxe7 Kxe7
19.d5 h6 20.Nf3 Bg4 21.Rac1 g5 22.h4 Bxf3
23.gxf3 gxh4 24.Kg2 c6 25.dxc6 Nxc6
26.f4 Nb4 27.Rcd1 Nxa2 (11.431.607) 2574

23/28 0:05 -2.22 16.Qh6 Qf8 17.Qxf8+ Kxf8 18.Nxe7 Kxe7
19.d5 h6 20.Nf3 Bd7 21.Rfc1 Rf8
22.Rc3 g5 23.h3 h5 24.Rf1 g4 25.Nh4 Rf6
26.hxg4 hxg4 27.Rcc1 g3 (14.926.409) 2577

24/28 0:07 -2.31-- 16.Qh6 Qf8 (18.466.728) 2630

24/31 0:07 -2.37-- 16.Qh6 Qf8 (20.057.161) 2653

24/31 0:08 -2.46-- 16.Qh6 Rg7 (23.026.163) 2674

24/31 0:08 -2.38++ 16.Qh6 (23.802.583) 2673

24/31 0:09 -2.49-- 16.Qh6 Rg7 (24.640.538) 2680

24/31 0:09 -2.60 16.Qh6 Rg7 17.e5 dxe5 18.Nxh7 Bxd4
19.Ndf6+ Kf7 20.Rac1 Nc6 21.Rfd1 Bf5
22.g4 Be6 23.a3 Qh8 24.Re1 Bxg4
25.Rb1 Rxh7 26.Nxh7 Qg7 27.Ng5+ Kg8
28.Qxg7+ Kxg7 29.Rxb7 (26.792.204) 2680

25/31 0:11 -2.70-- 16.Qh6 Rg7 (29.868.002) 2695

25/31 0:12 -2.76-- 16.Qh6 Rg7 (33.015.009) 2701

25/31 0:13 -2.69++ 16.Qh6 (35.549.673) 2707

25/31 0:14 -2.77-- 16.Qh6 Rg7 (38.329.191) 2714

25/31 0:14 -2.66++ 16.Qh6 (40.141.489) 2710

25/32 0:15 -2.82-- 16.Qh6 Rg7 (43.166.321) 2711

25/32 0:16 -2.58++ 16.Qh6 (43.812.114) 2708

25/32 0:16 -2.53 16.Qh6 Rg7 17.e5 dxe5 18.Nxh7 Rxh7
19.Qxg6+ Rg7 20.Nf6+ Kf8 21.Qh6 Nc6
22.dxe5 Bd4 23.Rad1 Be6 24.Rfe1 Qe7
25.Qf4 a5 26.Rxd4 Nxd4 27.Nh7+ Ke8
28.Nf6+ Kd8 29.Qxd4+ (44.664.436) 2706

26/32 0:18 -2.63-- 16.Qh6 Rg7 (50.509.486) 2723

26/32 0:19 -2.69-- 16.Qh6 Rg7 (52.278.063) 2729

26/32 0:20 -2.78-- 16.Qh6 Rg7 (55.809.111) 2727

26/33 0:23 -2.92-- 16.Qh6 Rg7 (63.343.433) 2732

26/34 0:27 -2.82 16.Qh6 Rg7 17.e5 dxe5 18.Nxh7 Bxd4
19.Ndf6+ Kf7 20.Rfd1 Nc4 21.Rab1 Bf5
22.Rbc1 Nb2 23.Rd2 (74.624.476) 2734

27/34 0:30 -2.93-- 16.Qh6 Rg7 (82.795.044) 2744

27/34 0:32 -2.99-- 16.Qh6 Rg7 (90.342.500) 2754

27/34 0:33 -2.92++ 16.Qh6 (91.910.793) 2749

27/34 0:33 -2.78++ 16.Qh6 (92.959.136) 2750

27/34 0:34 -2.72 16.Qh6 Rg7 17.e5 dxe5 18.Nxh7 Rxh7
19.Qxg6+ Rg7 20.Nf6+ Kf8 21.Qh6 Nc6
22.dxe5 Bd4 23.Rad1 Be6 24.Rfe1 Nxe5
25.Qf4 Rf7 26.Nh7+ Kg8 27.Qxd4 Qxd4
28.Rxd4 Rf5 29.Nf6+ (95.234.996) 2746

28/35 0:35 -2.66++ 16.Qh6 (98.126.808) 2737

28/35 0:36 -2.60++ 16.Qh6 (99.003.482) 2737

28/35 0:39 -2.67-- 16.Qh6 Rg7 (108.944.952) 2743

28/35 0:42 -2.81-- 16.Qh6 Rg7 (116.148.109) 2744

28/36 0:51 -3.02-- 16.Qh6 Rg7 (139.689.516) 2734

28/36 0:56 -3.04 16.Qh6 Rg7 17.e5 dxe5 18.Nxh7 Rxh7
19.Qxg6+ Rg7 20.Nf6+ Kf8 21.Qh6 Bh3
22.Nh5 Qg5 23.Qxg7+ Qxg7 24.Nxg7 Kxg7
25.gxh3 exd4 26.Rac1 c5 27.Rfe1 c4
28.Kg2 Rh8 29.Re6 (153.406.944) 2732

29/36 0:57 -2.98++ 16.Qh6 (158.455.092) 2737

29/36 1:02 -2.92++ 16.Nf6+ (170.541.947) 2747

29/36 1:03 -2.82++ 16.Nf6+ (172.961.030) 2743

29/36 1:03 -2.68++ 16.Nf6+ (174.445.152) 2741

29/36 1:04 -2.48++ 16.Nf6+ (177.849.209) 2741

29/36 1:05 -2.16++ 16.Nf6+ (180.781.854) 2742

29/44 1:06 -1.69++ 16.Nf6+ (181.882.047) 2742

29/44 1:07 -0.99++ 16.Nf6+ (184.537.294) 2744

29/46 1:09 0.00 16.Nf6+ Kg7 17.Qxh7+ Kxf6 18.e5+ Kxg5
19.f4+ Kf5 20.Qh3+ Ke4 21.Qf3+ Kf5
22.Qh3+ (190.793.941) 2744

30/46 1:12 0.00 16.Nf6+ Kg7 17.Qxh7+ Kxf6 18.e5+ Kxg5
19.f4+ Kf5 20.Qh3+ Ke4 21.Qf3+ Kf5
22.Qh3+ (198.123.578) 2738

31/46 1:14 0.00 16.Nf6+ Kg7 17.Qxh7+ Kxf6 18.e5+ Kxg5
19.f4+ Kf5 20.Qh3+ Ke4 21.Qf3+ Kf5
22.Qh3+ (203.612.249) 2739

32/46 1:18 0.00 16.Nf6+ Kg7 17.Qxh7+ Kxf6 18.e5+ Kxg5
19.f4+ Kf5 20.Qh3+ Ke4 21.Qf3+ Kf5
22.Qh3+ (215.338.585) 2739

33/46 1:24 0.00 16.Nf6+ Kg7 17.Qxh7+ Kxf6 18.e5+ Kxg5
19.f4+ Kf5 20.Qh3+ Ke4 21.Qf3+ Kf5
22.Qh3+ (231.371.189) 2742

34/46 1:33 0.00 16.Nf6+ Kg7 17.Qxh7+ Kxf6 18.e5+ Kxg5
19.f4+ Kf5 20.Qh3+ Ke4 21.Qf3+ Kf5
22.Qh3+ (256.895.682) 2753

35/46 1:41 0.00 16.Nf6+ Kg7 17.Qxh7+ Kxf6 18.e5+ Kxg5
19.f4+ Kf5 20.Qh3+ Ke4 21.Qf3+ Kf5
22.Qh3+ (279.085.410) 2746

36/46 2:00 0.00 16.Nf6+ Kg7 17.Qxh7+ Kxf6 18.e5+ Kxg5
19.f4+ Kf5 20.Qh3+ Ke4 21.Qf3+ Kf5
22.Qh3+ (334.526.088) 2779

37/46 2:22 0.00 16.Nf6+ Kg7 17.Qxh7+ Kxf6 18.e5+ Kxg5
19.f4+ Kf5 20.Qh3+ Ke4 21.Qf3+ Kf5
22.Qh3+ (399.966.144) 2804

38/46 2:38 0.00 16.Nf6+ Kg7 17.Qxh7+ Kxf6 18.e5+ Kxg5
19.f4+ Kf5 20.Qh3+ Ke4 21.Qf3+ Kf5
22.Qh3+ (445.742.035) 2808

39/46 3:01 0.00 16.Nf6+ Kg7 17.Qxh7+ Kxf6 18.e5+ Kxg5
19.f4+ Kf5 20.Qh3+ Ke4 21.Qf3+ Kf5
22.Qh3+ (515.031.273) 2830

40/46 3:50 0.00 16.Nf6+ Kg7 17.Qxh7+ Kxf6 18.e5+ Kxg5
19.f4+ Kf5 20.Qh3+ Ke4 21.Qf3+ Kf5
22.Qh3+ (665.189.582) 2883

best move: Nd5-f6 time: 4:18.666 min n/s: 2.883.728 nodes: 748.052.485

Hi Eelco,

really interesting. My analyzing branch finds it faster.

Code: Select all

info depth 21 seldepth 42 multipv 1 score cp 0 nodes 15816702 nps 1442208 tbhits 0 time 10967 pv d5f6 g8g7 h5h7 g7f6 e4e5 f6g5 f2f4 g5f5 h7h3 f5e4 h3f3 e4f5 f3h3

And the most significant change in this branch is the depth of the verification search!

[Joerg Oster]

Too low king psqt mg penalty?

SF seems to penalise d8/e8 squares 4 times more than d4/e4/d5/e5 squares, but if this is the right approach is not at all clear; ...

Lyudmil, it seems you misread the piece square tables.
For Black:
d8 = 225 (midgame)
d4 = 100 (midgame)

[Lyudmil Tsvetkov]

Too low king psqt mg penalty?

SF seems to penalise d8/e8 squares 4 times more than d4/e4/d5/e5 squares, but if this is the right approach is not at all clear; ...

Lyudmil, it seems you misread the piece square tables.
For Black:
d8 = 225 (midgame)
d4 = 100 (midgame)

I do not misread anything.
I already learned my lesson that SF counts ranks the other way as humans do.

225 vs 100, only 2-fold difference? And you think that is sufficient? d4 is an extremely dangerous square.

Besides, I was talking of the d8 square from white's point of view (on Eelco's diagram that would be the d1 square). SF has 25cps for d8, 4-fold penalty compared to d4/d5. You think this is the right approach?

Having penalty for d8 (from white's point of view) is almost meaningless, as the king rarely goes there. The d4/d5 penalty on the other hand is very useful, as, before arriving at d8, the white king should pass through d4/d5.

[kgburcham]

for Stockfish-5 the best move is: 13.Nxe7??

this version chooses Nf6

[d] r1bq2k1/ppp1r2p/1b1p2p1/n2N2NQ/3PP3/8/P4PPP/R4RK1 w - -

Engine: Stockfish 131214 64 BMI2 (8192 MB)
by Tord Romstad, Marco Costalba and Joona
1/02 0:00 -2.03 16.Nf6+ Kh8 (272) 272
2/03 0:00 -2.26 16.Nf6+ Kh8 17.Qd1 (828) 828
3/04 0:00 -2.71 16.Nf6+ Kh8 17.Qd1 Nc4 (1.166) 1166
4/05 0:00 -1.86 16.Qh4 Bd7 17.Nxe7+ Qxe7 18.Rac1 (4.764) 4764
5/06 0:00 -2.37 16.Qh4 Rg7 17.e5 dxe5 18.Nxb6 axb6 (7.302) 429
6/09 0:00 -2.37 16.Qh4 Rg7 17.e5 dxe5 18.Nxb6 axb6 (11.511) 677
7/09 0:00 -2.37 16.Qh4 Rg7 17.e5 dxe5 18.Nxb6 axb6 19.dxe5 (12.401) 729
8/09 0:00 -2.20 16.Nf6+ Kg7 17.Qh4 Bxd4 18.Ngxh7 Bxa1 19.Rxa1 Nc6 20.f3 (20.846) 1226
9/14 0:00 -2.20 16.Qh4 Rg7 17.Rfd1 c6 18.Nxb6 axb6 19.Rac1 Qf6 20.f3 (62.957) 1967
10/14 0:00 -2.32 16.Qh4 Rg7 17.e5 dxe5 18.Nxb6 axb6 19.dxe5 Be6 20.Rfd1 Qe7 21.Qf4 (93.452) 2920
11/15 0:00 -2.31 16.Qh4 Rf7 17.Qh6 Rg7 18.Rfd1 c6 19.Nxb6 axb6 20.e5 Nc4 21.Rdc1 d5 22.e6 (169.791) 3537
12/17 0:00 -2.50 16.Qh4 Rf7 17.Rfd1 c6 18.Nxb6 axb6 19.Rd3 h5 20.Qg3 Rg7 21.Qf4 Nc4 (284.353) 4443
13/20 0:00 -2.64 16.Qh4 Rf7 17.Rfd1 c6 18.Qh6 Rg7 19.Nxb6 axb6 20.d5 Qf6 21.Rac1 Re7 22.f3 Bd7 23.dxc6 bxc6 (555.571) 5005
14/24 0:00 -2.68 16.Qh4 Rf7 17.g3 Rg7 18.e5 dxe5 19.Nxb6 axb6 20.dxe5 Nc6 21.Rfe1 Nd4 22.e6 Re7 23.Nf7 (1.078.290) 6232
15/24 0:00 -2.77 16.Qh4 Rf7 17.Qg3 Rg7 18.Rfd1 c6 19.Nxb6 axb6 20.d5 h6 21.Nf3 Nc4 22.e5 Bf5 23.dxc6 bxc6 (1.544.347) 6543
16/34 0:00 -1.31 16.Nf6+ Kg7 17.Qxh7+ Kxf6 18.e5+ Kxg5 19.f4+ Kf5 20.Qh3+ Ke4 21.Qf3+ Kxd4 22.Rac1 Nc4 23.Rfd1+ Kc5 24.Qd5+ Kb4+ 25.Kh1 Nb2 26.Qb3+ Ka5 27.Rd5+ c5 28.Qxb2 Bf5 29.Qa3+ (2.538.698) 7358
17/37 0:00 -0.98 16.Nf6+ Kg7 17.Qxh7+ Kxf6 18.e5+ Kxg5 19.f4+ Kf5 20.Qh3+ Ke4 21.Qf3+ Kxd4 22.Rac1 Nc4 23.Rfd1+ Kc5 24.Qd5+ Kb4+ 25.Kh1 Nb2 26.Qb3+ Ka5 27.Rd5+ c5 28.Qxb2 Bf5 29.Rxd6 (2.646.330) 7330
18/41 0:00 0.00 16.Nf6+ Kg7 17.Qxh7+ Kxf6 18.e5+ Kxg5 19.f4+ Kf5 20.Qh3+ Ke4 21.Qf3+ Kf5 22.Qh3+ (3.264.073) 7435
19/41 0:00 0.00 16.Nf6+ Kg7 17.Qxh7+ Kxf6 18.e5+ Kxg5 19.f4+ Kf5 20.Qh3+ Ke4 21.Qf3+ Kf5 22.Qh3+ (3.588.303) 7634
20/41 0:00 0.00 16.Nf6+ Kg7 17.Qxh7+ Kxf6 18.e5+ Kxg5 19.f4+ Kf5 20.Qh3+ Ke4 21.Qf3+ Kf5 22.Qh3+ (3.882.120) 7748
21/41 0:00 0.00 16.Nf6+ Kg7 17.Qxh7+ Kxf6 18.e5+ Kxg5 19.f4+ Kf5 20.Qh3+ Ke4 21.Qf3+ Kf5 22.Qh3+ (4.133.226) 7769
22/41 0:00 0.00 16.Nf6+ Kg7 17.Qxh7+ Kxf6 18.e5+ Kxg5 19.f4+ Kf5 20.Qh3+ Ke4 21.Qf3+ Kf5 22.Qh3+ (4.438.575) 7869
23/41 0:00 0.00 16.Nf6+ Kg7 17.Qxh7+ Kxf6 18.e5+ Kxg5 19.f4+ Kf5 20.Qh3+ Ke4 21.Qf3+ Kf5 22.Qh3+ (5.127.792) 8392
24/41 0:00 0.00 16.Nf6+ Kg7 17.Qxh7+ Kxf6 18.e5+ Kxg5 19.f4+ Kf5 20.Qh3+ Ke4 21.Qf3+ Kf5 22.Qh3+ (6.348.037) 7798
25/41 0:00 0.00 16.Nf6+ Kg7 17.Qxh7+ Kxf6 18.e5+ Kxg5 19.f4+ Kf5 20.Qh3+ Ke4 21.Qf3+ Kf5 22.Qh3+ (7.942.302) 8187
26/41 0:01 0.00 16.Nf6+ Kg7 17.Qxh7+ Kxf6 18.e5+ Kxg5 19.f4+ Kf5 20.Qh3+ Ke4 21.Qf3+ Kf5 22.Qh3+ (9.305.377) 8624
27/41 0:01 0.00 16.Nf6+ Kg7 17.Qxh7+ Kxf6 18.e5+ Kxg5 19.f4+ Kf5 20.Qh3+ Ke4 21.Qf3+ Kf5 22.Qh3+ (12.235.902) 9426
28/41 0:01 0.00 16.Nf6+ Kg7 17.Qxh7+ Kxf6 18.e5+ Kxg5 19.f4+ Kf5 20.Qh3+ Ke4 21.Qf3+ Kf5 22.Qh3+ (15.890.373) 10160
29/41 0:02 0.00 16.Nf6+ Kg7 17.Qxh7+ Kxf6 18.e5+ Kxg5 19.f4+ Kf5 20.Qh3+ Ke4 21.Qf3+ Kf5 22.Qh3+ (29.078.362) 11922
30/41 0:03 0.00 16.Nf6+ Kg7 17.Qxh7+ Kxf6 18.e5+ Kxg5 19.f4+ Kf5 20.Qh3+ Ke4 21.Qf3+ Kf5 22.Qh3+ (37.237.613) 12217
31/41 0:03 0.00 16.Nf6+ Kg7 17.Qxh7+ Kxf6 18.e5+ Kxg5 19.f4+ Kf5 20.Qh3+ Ke4 21.Qf3+ Kf5 22.Qh3+ (45.441.789) 12696
32/41 0:04 0.00 16.Nf6+ Kg7 17.Qxh7+ Kxf6 18.e5+ Kxg5 19.f4+ Kf5 20.Qh3+ Ke4 21.Qf3+ Kf5 22.Qh3+ (54.950.751) 12926
33/41 0:05 0.00 16.Nf6+ Kg7 17.Qxh7+ Kxf6 18.e5+ Kxg5 19.f4+ Kf5 20.Qh3+ Ke4 21.Qf3+ Kf5 22.Qh3+ (65.667.647) 13047
34/41 0:07 0.00 16.Nf6+ Kg7 17.Qxh7+ Kxf6 18.e5+ Kxg5 19.f4+ Kf5 20.Qh3+ Ke4 21.Qf3+ Kf5 22.Qh3+ (106.237.486) 13569
35/41 0:11 0.00 16.Nf6+ Kg7 17.Qxh7+ Kxf6 18.e5+ Kxg5 19.f4+ Kf5 20.Qh3+ Ke4 21.Qf3+ Kf5 22.Qh3+ (168.343.646) 14498



[Event "?"]
[Site "?"]
[Date "2014.12.13"]
[Round "?"]
[White "?"]
[Black "?"]
[Result "*"]

1. e4 e5 2. Nf3 Nc6 3. Bc4 Bc5 4. b4 Bxb4 5. c3 Bc5 6. d4
exd4 7. O-O d6 8. cxd4 Bb6 9. Nc3 Na5 10. Bg5 Ne7 11. Bxf7+
Kxf7 12. Nd5 Re8 13. Bxe7 Rxe7 14. Ng5+ Kg8 15. Qh5 g6

[Joerg Oster]

Too low king psqt mg penalty?

SF seems to penalise d8/e8 squares 4 times more than d4/e4/d5/e5 squares, but if this is the right approach is not at all clear; ...

Lyudmil, it seems you misread the piece square tables.
For Black:
d8 = 225 (midgame)
d4 = 100 (midgame)

I do not misread anything.
I already learned my lesson that SF counts ranks the other way as humans do.

225 vs 100, only 2-fold difference? And you think that is sufficient? d4 is an extremely dangerous square.

Besides, I was talking of the d8 square from white's point of view (on Eelco's diagram that would be the d1 square). SF has 25cps for d8, 4-fold penalty compared to d4/d5. You think this is the right approach?

Having penalty for d8 (from white's point of view) is almost meaningless, as the king rarely goes there. The d4/d5 penalty on the other hand is very useful, as, before arriving at d8, the white king should pass through d4/d5.

I didn't notice you were talking about penalty from white's pov, while we were discussing a position with black king's placement ...
Sorry, my fault.

[Joerg Oster]

Hi Eelco,

I think the main problem is too aggressive LMR.
With a slight change I get this for the initial position:

Code: Select all

info depth 20 seldepth 38 multipv 1 score cp -127 lowerbound nodes 18273277 nps 1573925 tbhits 0 time 11610 pv g5e7
info depth 20 currmove g5e7 currmovenumber 1
info depth 20 seldepth 38 multipv 1 score cp -113 lowerbound nodes 18384488 nps 1574149 tbhits 0 time 11679 pv g5e7
info depth 20 currmove g5e7 currmovenumber 1
info depth 20 seldepth 38 multipv 1 score cp -92 lowerbound nodes 18462580 nps 1574096 tbhits 0 time 11729 pv g5e7
info depth 20 currmove g5e7 currmovenumber 1
info depth 20 seldepth 38 multipv 1 score cp -60 lowerbound nodes 18648575 nps 1573719 tbhits 0 time 11850 pv g5e7
info depth 20 currmove g5e7 currmovenumber 1
info depth 20 seldepth 38 multipv 1 score cp -13 lowerbound nodes 18904091 nps 1573374 tbhits 0 time 12015 pv g5e7
info depth 20 currmove g5e7 currmovenumber 1
info depth 20 currmove d5b6 currmovenumber 2
info depth 20 currmove d5e7 currmovenumber 3
info depth 20 currmove e4e5 currmovenumber 4
info depth 20 currmove d1d3 currmovenumber 5
info depth 20 currmove f1e1 currmovenumber 6
info depth 20 currmove g5e3 currmovenumber 7
info depth 20 currmove f3h4 currmovenumber 8
info depth 20 currmove d5f6 currmovenumber 9
info depth 20 currmove g5h4 currmovenumber 10
info depth 20 currmove d5f4 currmovenumber 11
info depth 20 currmove d1d2 currmovenumber 12
info depth 20 currmove h2h4 currmovenumber 13
info depth 20 currmove d1b3 currmovenumber 14
info depth 20 currmove g2g4 currmovenumber 15
info depth 20 currmove d1e1 currmovenumber 16
info depth 20 currmove d1c1 currmovenumber 17
info depth 20 currmove h2h3 currmovenumber 18
info depth 20 currmove g2g3 currmovenumber 19
info depth 20 currmove d1e2 currmovenumber 20
info depth 20 currmove f3e5 currmovenumber 21
info depth 20 currmove f3d2 currmovenumber 22
info depth 20 currmove d1c2 currmovenumber 23
info depth 20 currmove d1a4 currmovenumber 24
info depth 20 currmove d5c3 currmovenumber 25
info depth 20 currmove a2a4 currmovenumber 26
info depth 20 currmove g5f6 currmovenumber 27
info depth 20 currmove g5h6 currmovenumber 28
info depth 20 currmove a1b1 currmovenumber 29
info depth 20 currmove a1c1 currmovenumber 30
info depth 20 currmove g5d2 currmovenumber 31
info depth 20 currmove d1b1 currmovenumber 32
info depth 20 currmove g1h1 currmovenumber 33
info depth 20 currmove d5e3 currmovenumber 34
info depth 20 currmove g5c1 currmovenumber 35
info depth 20 currmove g5f4 currmovenumber 36
info depth 20 currmove d5b4 currmovenumber 37
info depth 20 currmove f3e1 currmovenumber 38
info depth 20 currmove a2a3 currmovenumber 39
info depth 20 currmove d5c7 currmovenumber 40
info depth 20 seldepth 38 multipv 1 score cp 0 nodes 19374823 nps 1575445 tbhits 0 time 12298 pv g5e7 e8e7 f3g5 f7g8 d1h5 g7g6 d5f6 g8g7 h5h7 g7f6 e4e5 f6g5 f2f4 g5f5 h7h3 f5e4 h3f3 e4d4 a1c1 a5c4 f1d1 d4c5 f3d5 c5b4 g1h1 c4b2 d5e4 b4b5 e4e2 b5a5 e2d2 a5b5 d2e2