[d]8/4k3/8/1p1p1p1p/pPpPpPpP/P1P1P1P1/8/6BK w - - 0 1
after 99 plies no more output in next hour even if CPU usage is still 100%
analysis by Stockfish 121119 64 BMI2:
...
1.Bf2 Ke6 2.Kg1 Kd6 3.Be1 Ke6 4.Kf2 Ke7 5.Kf1 Kf6 6.Ke2 Ke6 7.Bd2 Kd7 8.Kf2 Ke6 9.Kf1 Ke7 10.Kg2 Kf6 11.Kh2 Ke7 12.Kh1 Ke6 13.Bc1 Kd6 14.Kg2 Ke7 15.Kf2 Kd6 16.Ke1 Kd7 17.Kf1 Kd6 18.Kf2 Ke6 19.Ke2 Ke7 20.Kd1 Kd7 21.Kc2 Kd6 22.Bd2 Kd7 23.Be1 Kd6 24.Bf2 Kd7 25.Kc1 Kd6 26.Kd2 Kd7 27.Kc2 Kd6 28.Be1 Ke6 29.Kb2 Kd7 30.Kb1 Kd6 31.Ka2 Ke6 32.Bf2 Kd6 33.Bg1 Kd7 34.Kb1 Kd6 35.Kb2 Ke6 36.Kc2 Kd6 37.Kd2 Kc6 38.Ke2 Kd7 39.Kf2 Ke6 40.Bh2 Kf6 41.Kg2 Ke7 42.Bg1 Kd7 43.Bf2 Kd6 44.Be1 Ke6 45.Kg1 Kd6 46.Bd2 Ke7 47.Kh2 Ke6 48.Kh1 Ke7 49.Be1 Kd7
+- (2.58) Depth: 98/98 00:00:06 71739kN
nothing
nothing
...
Something is wrong, when MAX_PLY is 246.
Stockfish search stops here after 99 plies, why?
Moderators: hgm, Rebel, chrisw
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- Full name: Henk Drost
Re: Stockfish search stops here after 99 plies, why?
It hasn't stopped though.
It just can't detect the fortress and thinks it has an advantage.
After 99 plies it's desperately trying to find the combination that doesn't draw. Since this position is 100% locked up and Stockfish has no fortress detection it's brute forcing it.
It will take a very long time before Stockfish reaches 100 ply depth and properly evaluates the position as a draw.
It just can't detect the fortress and thinks it has an advantage.
After 99 plies it's desperately trying to find the combination that doesn't draw. Since this position is 100% locked up and Stockfish has no fortress detection it's brute forcing it.
It will take a very long time before Stockfish reaches 100 ply depth and properly evaluates the position as a draw.
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Re: Stockfish search stops here after 99 plies, why?
After 99 plies SF failed low (suddenly discovering the 50 move draw). Then it starts researching the position at lower depth. But in order not to confuse the user it does not print those lower depths. That's why it does not print anything.Jouni wrote: ↑Thu Nov 14, 2019 8:52 am [d]8/4k3/8/1p1p1p1p/pPpPpPpP/P1P1P1P1/8/6BK w - - 0 1
after 99 plies no more output in next hour even if CPU usage is still 100%
analysis by Stockfish 121119 64 BMI2:
...
1.Bf2 Ke6 2.Kg1 Kd6 3.Be1 Ke6 4.Kf2 Ke7 5.Kf1 Kf6 6.Ke2 Ke6 7.Bd2 Kd7 8.Kf2 Ke6 9.Kf1 Ke7 10.Kg2 Kf6 11.Kh2 Ke7 12.Kh1 Ke6 13.Bc1 Kd6 14.Kg2 Ke7 15.Kf2 Kd6 16.Ke1 Kd7 17.Kf1 Kd6 18.Kf2 Ke6 19.Ke2 Ke7 20.Kd1 Kd7 21.Kc2 Kd6 22.Bd2 Kd7 23.Be1 Kd6 24.Bf2 Kd7 25.Kc1 Kd6 26.Kd2 Kd7 27.Kc2 Kd6 28.Be1 Ke6 29.Kb2 Kd7 30.Kb1 Kd6 31.Ka2 Ke6 32.Bf2 Kd6 33.Bg1 Kd7 34.Kb1 Kd6 35.Kb2 Ke6 36.Kc2 Kd6 37.Kd2 Kc6 38.Ke2 Kd7 39.Kf2 Ke6 40.Bh2 Kf6 41.Kg2 Ke7 42.Bg1 Kd7 43.Bf2 Kd6 44.Be1 Ke6 45.Kg1 Kd6 46.Bd2 Ke7 47.Kh2 Ke6 48.Kh1 Ke7 49.Be1 Kd7
+- (2.58) Depth: 98/98 00:00:06 71739kN
nothing
nothing
...
Something is wrong, when MAX_PLY is 246.
Ideas=science. Simplification=engineering.
Without ideas there is nothing to simplify.
Without ideas there is nothing to simplify.
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Re: Stockfish search stops here after 99 plies, why?
Assumimg that Stockfish really sees the 50 move rule here, it should but I can't remember Stockfish actually doing this myself, but then it will find that every value other than a draw is wrong. Because even with only three pieces moving there are a lot of transpositions all with the same value because of the material plus for White, all the values in hash are wrong. All moves have the same value still but now should all have VALUE_DRAW. This can take forever to correct. Stockfish simply 'never' returns to the root at least not in foreseeable time That would be my guess IID should help as Michel says but probably it's out of its depth here, does not change much in the time? I have not read the fortress discussion Jouni mentioned, probably they have better answers there? Basically this is a fortress so you should see it with any fortress, only not everywhere SF can reach 100 plies deep.
Debugging is twice as hard as writing the code in the first
place. Therefore, if you write the code as cleverly as possible, you
are, by definition, not smart enough to debug it.
-- Brian W. Kernighan
place. Therefore, if you write the code as cleverly as possible, you
are, by definition, not smart enough to debug it.
-- Brian W. Kernighan
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Re: Stockfish search stops here after 99 plies, why?
A different way of analysing positions such as this one is required.
Since the Black king could only be on 24 different squares in any game played from this position and the White bishop on only 8 different squares, leaving only 15 different squares for the White king, there would be only 24x8x15=2880 positions that could occur in the game.
Since none of these 2880 positions would be a checkmate, the game is drawn.
It should be fairly trivial for a chess program to detect this if it was looking for it.
e.g. find all the possible squares for any pieces that can be moved.
Create a set of all possible future positions.
Check each position for checkmate at depth 0
If no checkmate is found for any of the positions, the original position is a draw.
I'm not suggesting it is practical to use this method at all, but it would work in similar fortress positions which humans immediately see as drawn and computers do not.
Since the Black king could only be on 24 different squares in any game played from this position and the White bishop on only 8 different squares, leaving only 15 different squares for the White king, there would be only 24x8x15=2880 positions that could occur in the game.
Since none of these 2880 positions would be a checkmate, the game is drawn.
It should be fairly trivial for a chess program to detect this if it was looking for it.
e.g. find all the possible squares for any pieces that can be moved.
Create a set of all possible future positions.
Check each position for checkmate at depth 0
If no checkmate is found for any of the positions, the original position is a draw.
I'm not suggesting it is practical to use this method at all, but it would work in similar fortress positions which humans immediately see as drawn and computers do not.
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- Full name: Karlo Balla
Re: Stockfish search stops here after 99 plies, why?
The behavior of SF is perfectly sound.Jouni wrote: ↑Thu Nov 14, 2019 8:52 am [d]8/4k3/8/1p1p1p1p/pPpPpPpP/P1P1P1P1/8/6BK w - - 0 1
after 99 plies no more output in next hour even if CPU usage is still 100%
analysis by Stockfish 121119 64 BMI2:
...
1.Bf2 Ke6 2.Kg1 Kd6 3.Be1 Ke6 4.Kf2 Ke7 5.Kf1 Kf6 6.Ke2 Ke6 7.Bd2 Kd7 8.Kf2 Ke6 9.Kf1 Ke7 10.Kg2 Kf6 11.Kh2 Ke7 12.Kh1 Ke6 13.Bc1 Kd6 14.Kg2 Ke7 15.Kf2 Kd6 16.Ke1 Kd7 17.Kf1 Kd6 18.Kf2 Ke6 19.Ke2 Ke7 20.Kd1 Kd7 21.Kc2 Kd6 22.Bd2 Kd7 23.Be1 Kd6 24.Bf2 Kd7 25.Kc1 Kd6 26.Kd2 Kd7 27.Kc2 Kd6 28.Be1 Ke6 29.Kb2 Kd7 30.Kb1 Kd6 31.Ka2 Ke6 32.Bf2 Kd6 33.Bg1 Kd7 34.Kb1 Kd6 35.Kb2 Ke6 36.Kc2 Kd6 37.Kd2 Kc6 38.Ke2 Kd7 39.Kf2 Ke6 40.Bh2 Kf6 41.Kg2 Ke7 42.Bg1 Kd7 43.Bf2 Kd6 44.Be1 Ke6 45.Kg1 Kd6 46.Bd2 Ke7 47.Kh2 Ke6 48.Kh1 Ke7 49.Be1 Kd7
+- (2.58) Depth: 98/98 00:00:06 71739kN
nothing
nothing
...
Something is wrong, when MAX_PLY is 246.
At play 99 it starts to kick in the 50 move rule. At that moment SF realizes that the entire tree is wrong, so start to build it up from scratch.
The score of PV drops to zero. The next move is a potential PV with a score >2.0. This move also drops to zero, and so on. Every move is searched as PV, which means without reductions!!!
Best Regards,
Karlo Balla Jr.
Karlo Balla Jr.
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Re: Stockfish search stops here after 99 plies, why?
An engine with fortress detection doesn't need 100 plies to see the draw ( Scoring % output)Jouni wrote: ↑Thu Nov 14, 2019 8:52 am [d]8/4k3/8/1p1p1p1p/pPpPpPpP/P1P1P1P1/8/6BK w - - 0 1
after 99 plies no more output in next hour even if CPU usage is still 100%
analysis by Stockfish 121119 64 BMI2:
...
1.Bf2 Ke6 2.Kg1 Kd6 3.Be1 Ke6 4.Kf2 Ke7 5.Kf1 Kf6 6.Ke2 Ke6 7.Bd2 Kd7 8.Kf2 Ke6 9.Kf1 Ke7 10.Kg2 Kf6 11.Kh2 Ke7 12.Kh1 Ke6 13.Bc1 Kd6 14.Kg2 Ke7 15.Kf2 Kd6 16.Ke1 Kd7 17.Kf1 Kd6 18.Kf2 Ke6 19.Ke2 Ke7 20.Kd1 Kd7 21.Kc2 Kd6 22.Bd2 Kd7 23.Be1 Kd6 24.Bf2 Kd7 25.Kc1 Kd6 26.Kd2 Kd7 27.Kc2 Kd6 28.Be1 Ke6 29.Kb2 Kd7 30.Kb1 Kd6 31.Ka2 Ke6 32.Bf2 Kd6 33.Bg1 Kd7 34.Kb1 Kd6 35.Kb2 Ke6 36.Kc2 Kd6 37.Kd2 Kc6 38.Ke2 Kd7 39.Kf2 Ke6 40.Bh2 Kf6 41.Kg2 Ke7 42.Bg1 Kd7 43.Bf2 Kd6 44.Be1 Ke6 45.Kg1 Kd6 46.Bd2 Ke7 47.Kh2 Ke6 48.Kh1 Ke7 49.Be1 Kd7
+- (2.58) Depth: 98/98 00:00:06 71739kN
nothing
nothing
...
Something is wrong, when MAX_PLY is 246.
Honey-XR7-FD
Code: Select all
dep score nodes time (not shown: tbhits knps seldep)
101 +50.00 8.04G 3:54.25 Bf2 Kd7 Be1 Kc6 Bf2
100 +50.00 7.87G 3:48.82 Bf2 Ke6 Be1 Kd6 Bf2
99 +50.00 7.37G 3:33.63 Bf2 Kf6 Be1 Ke7
98 +50.00 7.02G 3:23.07 Bf2 Kf6 Be1 Kg6 Bf2
97 +50.00 6.72G 3:13.90 Bf2 Ke6 Kg2 Kd6 Kh1
96 +50.00 6.56G 3:09.24 Bf2 Ke6 Kg2 Kd7 Kh1
95 +50.00 6.38G 3:03.71 Bf2 Ke6 Kg2 Ke7
94 +50.00 5.87G 2:48.20 Bf2 Kd7 Kg2 Ke7
93 +50.00 5.71G 2:43.16 Bf2 Kd7 Kg2 Ke6 Bg1 Kf7 Kf2 Kg8 Kg2
92 +50.00 5.55G 2:38.40 Bf2 Ke6 Kg2 Kd6 Bg1 Ke6
91 +50.00 4.68G 2:12.57 Bf2 Kd7 Kg2 Ke6 Bg1 Kf6 Kf2 Ke6
90 +50.00 4.43G 2:04.99 Bf2 Kd7 Kg2 Kc6 Bg1 Kd7
89 +50.00 3.90G 1:49.47 Bf2 Kd6 Kg2 Kd7 Bg1 Kd6
88 +50.00 2.98G 1:22.36 Bf2 Kd7 Kg2 Ke6 Be1 Kd6 Bd2 Ke6
87 +50.00 2.27G 1:01.85 Bf2 Ke6 Kg2 Kd6 Be1 Kc6 Bf2
86 +50.00 2.04G 0:55.02 Bf2 Kd7 Kg2 Ke6 Be1 Kd6 Bd2 Ke7 Be1
85 +50.00 1.93G 0:51.80 Bf2 Kd7 Kg2 Kd6 Be1 Ke7 Kf2 Kd6
84 +50.00 1.82G 0:48.91 Bf2 Kd7 Kg2 Ke6 Be1 Kd6 Bd2 Ke6
83 +50.00 1.78G 0:47.54 Bf2 Kd7 Kg2 Ke6 Be1 Kd6 Bd2 Kc7 Bc1 Kc6 Bb2 Kb7 Kf2 Ka6 Ba1 Ka7 Bb2
82 +50.00 1.68G 0:44.62 Bf2 Kd7 Kg2 Kc6 Be1 Kd6 Bd2 Ke6 Be1
81 +50.00 1.59G 0:42.31 Bf2 Kd7 Kg2 Kd6 Be1 Ke6 Bf2
80 +50.00 1.55G 0:41.20 Bf2 Kd7 Kg2 Ke6 Be1 Kd6 Bd2 Kc6 Be1
79 +50.00 1.52G 0:40.20 Bf2 Kd7 Kg2 Kc7 Bg1 Kb7 Bf2
78 +50.00 1.49G 0:39.39 Bf2 Kd7 Kg2 Kd6 Be1 Ke6 Kf2 Kd6
77 +50.00 1.41G 0:37.15 Bf2 Kd7 Kg2 Kd6 Be1 Kc7 Kf2 Kc6 Ke2 Kd7 Kd2 Kc6
76 +50.00 1.35G 0:35.40 Bf2 Kd6 Bg1 Ke6 Kg2 Kd7 Kf2 Kd6 Ke2 Ke7 Kd2 Kd7 Bf2 Ke7
75 +50.00 1.30G 0:34.23 Bf2 Kd7 Kg2 Kd6 Be1 Ke6 Kf2 Kd6
74 +50.00 1.25G 0:32.73 Bf2 Ke6 Kg2 Kd6 Be1 Ke6
73 +50.00 1.22G 0:31.79 Bf2 Kd7 Kg2 Kd6 Be1 Ke6 Kf2 Kd6
72 +50.00 1.18G 0:30.82 Bf2 Ke6 Kg2 Kd6 Be1 Ke6
71 +50.00 1.04G 0:27.09 Bf2 Ke6 Kg2 Kd6 Be1 Kc6 Kh1 Kd6
70 +50.00 982.9M 0:25.50 Bf2 Ke6 Kg2 Kd6 Be1 Kc6 Kh1 Kd7 Bd2 Ke7 Be1
69 +50.00 940.1M 0:24.32 Bf2 Ke6 Kg2 Kd6 Be1 Ke6
68 +50.00 812.8M 0:20.92 Bf2 Ke6 Kg2 Kd6 Be1 Ke6
67 +50.00 753.4M 0:19.33 Bf2 Ke6 Kg2 Kd6 Be1 Kc7 Bf2
66 +50.00 683.6M 0:17.51 Bf2 Ke6 Kg2 Kd6 Be1 Ke6
65 +50.00 598.7M 0:15.28 Bf2 Ke6 Kg2 Kd7 Bg1 Kd6 Kf2 Kd7
64 +50.00 537.2M 0:13.66 Bf2 Ke6 Kg2 Kd6 Be1 Ke7 Bd2 Kd6
63 +50.00 425.4M 0:10.76 Bf2 Ke6 Kg2 Kd6 Be1 Ke6
62 +50.00 364.0M 0:09.17 Bf2 Ke6 Kg2 Kd6 Be1 Kd7 Kf2 Kd6
61 +50.00 331.3M 0:08.31 Bf2 Ke6 Kg2 Kd6 Be1 Ke6
60 +50.00 295.9M 0:07.41 Bf2 Ke6 Kg2 Kd6 Be1 Ke6
59 +50.00 253.0M 0:06.32 Bf2 Ke6 Kg2 Kd6 Be1 Kc6 Bd2 Kb7 Kf2 Kb6 Bc1 Kc7 Bb2 Kd6 Ke1 Ke6 Bc1 Kd6
58 +50.00 215.4M 0:05.38 Bf2 Ke6 Kg2 Kd7 Bg1 Kc6 Bh2 Kb6 Bg1
57 +50.00 191.6M 0:04.76 Bf2 Ke6 Kg2 Kd7 Bg1 Ke6
56 +50.00 159.9M 0:03.96 Bf2 Ke6 Kg2 Kd7 Bg1 Ke6
55 +50.00 139.7M 0:03.46 Bf2 Ke6 Kg2 Kd7 Bg1 Ke6
54 +50.00 122.1M 0:03.03 Bf2 Ke6 Kg2 Kd7 Bg1 Ke6
53 +50.00 105.2M 0:02.62 Bf2 Ke6 Kg2 Kd7 Bg1 Ke6
52 +50.00 88.6M 0:02.20 Bf2 Ke6 Kg2 Kd7 Bg1 Ke8 Kf2 Ke7 Ke2 Kd7 Kd2 Kc6 Bf2 Kc7 Be1 Kd7 Bf2
51 +50.00 72.3M 0:01.80 Bf2 Ke6 Kg2 Kd7 Bg1 Ke6
50 +50.00 61.1M 0:01.53 Bf2 Ke6 Kg2 Kd7 Bg1 Ke6
49 +50.00 53.5M 0:01.34 Bf2 Ke6 Kg2 Kd7 Bg1 Ke6
48 +50.00 39.0M 0:00.99 Bf2 Ke6 Kg2 Kd7 Bg1 Ke6
47 +50.00 31.8M 0:00.81 Bf2 Ke6 Kg2 Kd7 Bg1 Ke6
46 +50.00 23.7M 0:00.60 Bf2 Ke6 Kg2 Kd7 Bg1 Ke6
45 +50.00 17.8M 0:00.45 Bf2 Ke6 Kg2 Kd7 Bg1 Ke6
44 +50.00 15.1M 0:00.38 Bf2 Ke6 Kg2 Kd7 Bg1 Ke6
43 +50.00 12.6M 0:00.32 Bf2 Ke6 Kg2 Kd7 Bg1 Ke6
42 +50.00 10.5M 0:00.27 Bf2 Ke6 Kg2 Kd7 Bg1 Ke6
41 +50.00 8.68M 0:00.22 Bf2 Ke6 Kg2 Kd7 Bg1 Ke6
40 +50.00 7.54M 0:00.19 Bf2 Ke6 Kg2 Kd7 Bg1 Ke6
39 +50.00 5.17M 0:00.14 Bf2 Ke6 Kg2 Kd7 Bg1 Ke6
38 +50.00 4.16M 0:00.11 Bf2 Ke6 Kg2 Kd7 Bg1 Ke6
37 +50.00 3.36M 0:00.09 Bf2 Ke6 Kg2 Kd7 Bg1 Ke6
36 +50.00 2.47M 0:00.07 Bf2 Ke6 Kg2 Kd7 Bg1 Ke6
35 +50.00 2.00M 0:00.06 Bf2 Ke6 Kg2 Kd7 Bg1 Ke6
34 +50.00 1.80M 0:00.05 Bf2 Ke6 Kg2 Kd7 Bg1 Ke6
33 +50.00 1.44M 0:00.04 Bf2 Ke6 Kg2 Kd7 Bg1 Ke6
32 +50.00 1.13M 0:00.03 Bf2 Ke6 Kg2 Kd7 Bg1 Ke6
31 +50.00 838638 0:00.02 Bf2 Ke6 Kg2 Kd7 Bg1 Ke6
30 +50.00 641960 0:00.02 Bf2 Ke6 Kg2 Kd7 Bg1 Ke6
29 +50.00 553002 0:00.02 Bf2 Ke6 Kg2 Kd7 Bg1 Ke6
28 +50.00 474090 0:00.02 Bf2 Ke6 Kg2 Kd7 Bg1 Ke6
27 +50.00 360224 0:00.01 Bf2 Ke6 Kg2 Kd7 Bg1 Ke6
26 +50.00 309896 0:00.01 Bf2 Ke6 Kg2 Kd7 Bg1 Ke6
25 +50.00 298094 0:00.01 Bf2 Ke6 Kg2 Kd7 Bg1 Ke6
24 +50.00 270102 0:00.01 Bf2 Ke6 Kg2 Kd7 Bg1 Ke6
23 +50.00 230474 0:00.01 Bf2 Ke6 Kg2 Kd7 Bg1 Ke6
22 +50.00 189380 0:00.01 Bf2 Ke6 Kg2 Ke7
21 +50.00 162240 0:00.01 Bf2 Ke6 Kg2 Kd7 Bg1 Ke6
20 +50.00 154038 0:00.01 Bf2 Ke6 Kg2 Kd7 Bg1 Ke6
19 +50.00 141144 0:00.01 Bf2 Ke6 Kg2 Ke7
18 +50.00 126535 0:00.01 Bf2 Ke6 Kg2 Ke7
17 +50.00 113448 0:00.01 Bf2 Ke6 Kg2 Ke7
16 +50.00 100209 0:00.00 Bf2 Ke6 Kg2 Ke7
15 +50.00 90995 0:00.00 Bf2 Ke6 Kg2 Ke7
14 +50.00 86009 0:00.00 Bf2 Ke6 Kg2 Ke7
13 +50.00 82581 0:00.00 Bf2 Ke6 Kg2 Ke7
12 +50.00 78032 0:00.00 Bf2 Ke6 Kg2 Ke7
11 +50.00 75022 0:00.00 Bf2 Ke6 Kg2 Ke7
10 +50.00 71756 0:00.00 Bf2 Ke6 Kg2 Kd6 Bg1 Kd7 Kf2 Ke7 Ke2 Ke6
9 +50.00 69751 0:00.00 Bf2 Ke6 Kg2 Kd6 Bg1 Kd7 Kf2 Ke7 Ke2
8 +50.00 67865 0:00.00 Bf2 Ke6 Kg2 Kd6 Bg1 Kd7 Kf2 Ke7
7 +72.70 17685 0:00.00 Bf2 Kf6 Be1 Ke6 Kh2 Ke7 Kg2
6 +72.07 12308 0:00.00 Bf2 Kf6 Kh2 Kf7 Kg2
5 +70.93 5884 0:00.00 Bf2 Kf6 Kh2 Ke6 Kg2
4 +71.30 4605 0:00.00 Bf2 Kf6 Kh2
3 +71.27 3097 0:00.00 Kg2 Ke6 Bf2
2 +70.83 1898 0:00.00 Kg2 Kf6
1 +72.70 338 0:00.00 Kg2
1 Found 1511 tablebases
0 #
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Re: Stockfish search stops here after 99 plies, why?
An engine that works correctly does not need 100 plies to see the draw even with no fortress detection.
It is enough to see that the number of possible positions after 26 plies is equal to the number of possible positions after 28 plies when no position is mate to get the conclusion that it is a draw.
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Re: Stockfish search stops here after 99 plies, why?
OK no bug here but search explosion. BTW Crystal is clever and scores this fast 0,00:
Analysis by Crystal 270819 64 BMI2:
...
1.Bf2 Kd6 2.Kg1 Ke6 3.Kg2 Ke7
= (0.00) Depth: 34/14 00:00:01 23616kN
1.Bf2 Kd6 2.Kg1 Ke6 3.Be1 Kd7 4.Kf2 Kd6 5.Bd2 Ke7 6.Kf1 Kd6
= (0.00) Depth: 35/14 00:00:03 55612kN
1.Bf2 Kd6 2.Kg1 Kd7 3.Kg2 Ke7
= (0.00) Depth: 36/16 00:00:06 94670kN
Analysis by Crystal 270819 64 BMI2:
...
1.Bf2 Kd6 2.Kg1 Ke6 3.Kg2 Ke7
= (0.00) Depth: 34/14 00:00:01 23616kN
1.Bf2 Kd6 2.Kg1 Ke6 3.Be1 Kd7 4.Kf2 Kd6 5.Bd2 Ke7 6.Kf1 Kd6
= (0.00) Depth: 35/14 00:00:03 55612kN
1.Bf2 Kd6 2.Kg1 Kd7 3.Kg2 Ke7
= (0.00) Depth: 36/16 00:00:06 94670kN
Jouni
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Re: Stockfish search stops here after 99 plies, why?
Hi Mike,MikeB wrote: ↑Sat Nov 16, 2019 7:14 am
An engine with fortress detection doesn't need 100 plies to see the draw ( Scoring % output)
Honey-XR7-FDCode: Select all
dep score nodes time (not shown: tbhits knps seldep) 101 +50.00 8.04G 3:54.25 Bf2 Kd7 Be1 Kc6 Bf2 100 +50.00 7.87G 3:48.82 Bf2 Ke6 Be1 Kd6 Bf2 99 +50.00 7.37G 3:33.63 Bf2 Kf6 Be1 Ke7 98 +50.00 7.02G 3:23.07 Bf2 Kf6 Be1 Kg6 Bf2 97 +50.00 6.72G 3:13.90 Bf2 Ke6 Kg2 Kd6 Kh1 96 +50.00 6.56G 3:09.24 Bf2 Ke6 Kg2 Kd7 Kh1 95 +50.00 6.38G 3:03.71 Bf2 Ke6 Kg2 Ke7 94 +50.00 5.87G 2:48.20 Bf2 Kd7 Kg2 Ke7 93 +50.00 5.71G 2:43.16 Bf2 Kd7 Kg2 Ke6 Bg1 Kf7 Kf2 Kg8 Kg2 92 +50.00 5.55G 2:38.40 Bf2 Ke6 Kg2 Kd6 Bg1 Ke6 91 +50.00 4.68G 2:12.57 Bf2 Kd7 Kg2 Ke6 Bg1 Kf6 Kf2 Ke6 90 +50.00 4.43G 2:04.99 Bf2 Kd7 Kg2 Kc6 Bg1 Kd7 89 +50.00 3.90G 1:49.47 Bf2 Kd6 Kg2 Kd7 Bg1 Kd6 88 +50.00 2.98G 1:22.36 Bf2 Kd7 Kg2 Ke6 Be1 Kd6 Bd2 Ke6 87 +50.00 2.27G 1:01.85 Bf2 Ke6 Kg2 Kd6 Be1 Kc6 Bf2 86 +50.00 2.04G 0:55.02 Bf2 Kd7 Kg2 Ke6 Be1 Kd6 Bd2 Ke7 Be1 85 +50.00 1.93G 0:51.80 Bf2 Kd7 Kg2 Kd6 Be1 Ke7 Kf2 Kd6 84 +50.00 1.82G 0:48.91 Bf2 Kd7 Kg2 Ke6 Be1 Kd6 Bd2 Ke6 83 +50.00 1.78G 0:47.54 Bf2 Kd7 Kg2 Ke6 Be1 Kd6 Bd2 Kc7 Bc1 Kc6 Bb2 Kb7 Kf2 Ka6 Ba1 Ka7 Bb2 82 +50.00 1.68G 0:44.62 Bf2 Kd7 Kg2 Kc6 Be1 Kd6 Bd2 Ke6 Be1 81 +50.00 1.59G 0:42.31 Bf2 Kd7 Kg2 Kd6 Be1 Ke6 Bf2 80 +50.00 1.55G 0:41.20 Bf2 Kd7 Kg2 Ke6 Be1 Kd6 Bd2 Kc6 Be1 79 +50.00 1.52G 0:40.20 Bf2 Kd7 Kg2 Kc7 Bg1 Kb7 Bf2 78 +50.00 1.49G 0:39.39 Bf2 Kd7 Kg2 Kd6 Be1 Ke6 Kf2 Kd6 77 +50.00 1.41G 0:37.15 Bf2 Kd7 Kg2 Kd6 Be1 Kc7 Kf2 Kc6 Ke2 Kd7 Kd2 Kc6 76 +50.00 1.35G 0:35.40 Bf2 Kd6 Bg1 Ke6 Kg2 Kd7 Kf2 Kd6 Ke2 Ke7 Kd2 Kd7 Bf2 Ke7 75 +50.00 1.30G 0:34.23 Bf2 Kd7 Kg2 Kd6 Be1 Ke6 Kf2 Kd6 74 +50.00 1.25G 0:32.73 Bf2 Ke6 Kg2 Kd6 Be1 Ke6 73 +50.00 1.22G 0:31.79 Bf2 Kd7 Kg2 Kd6 Be1 Ke6 Kf2 Kd6 72 +50.00 1.18G 0:30.82 Bf2 Ke6 Kg2 Kd6 Be1 Ke6 71 +50.00 1.04G 0:27.09 Bf2 Ke6 Kg2 Kd6 Be1 Kc6 Kh1 Kd6 70 +50.00 982.9M 0:25.50 Bf2 Ke6 Kg2 Kd6 Be1 Kc6 Kh1 Kd7 Bd2 Ke7 Be1 69 +50.00 940.1M 0:24.32 Bf2 Ke6 Kg2 Kd6 Be1 Ke6 68 +50.00 812.8M 0:20.92 Bf2 Ke6 Kg2 Kd6 Be1 Ke6 67 +50.00 753.4M 0:19.33 Bf2 Ke6 Kg2 Kd6 Be1 Kc7 Bf2 66 +50.00 683.6M 0:17.51 Bf2 Ke6 Kg2 Kd6 Be1 Ke6 65 +50.00 598.7M 0:15.28 Bf2 Ke6 Kg2 Kd7 Bg1 Kd6 Kf2 Kd7 64 +50.00 537.2M 0:13.66 Bf2 Ke6 Kg2 Kd6 Be1 Ke7 Bd2 Kd6 63 +50.00 425.4M 0:10.76 Bf2 Ke6 Kg2 Kd6 Be1 Ke6 62 +50.00 364.0M 0:09.17 Bf2 Ke6 Kg2 Kd6 Be1 Kd7 Kf2 Kd6 61 +50.00 331.3M 0:08.31 Bf2 Ke6 Kg2 Kd6 Be1 Ke6 60 +50.00 295.9M 0:07.41 Bf2 Ke6 Kg2 Kd6 Be1 Ke6 59 +50.00 253.0M 0:06.32 Bf2 Ke6 Kg2 Kd6 Be1 Kc6 Bd2 Kb7 Kf2 Kb6 Bc1 Kc7 Bb2 Kd6 Ke1 Ke6 Bc1 Kd6 58 +50.00 215.4M 0:05.38 Bf2 Ke6 Kg2 Kd7 Bg1 Kc6 Bh2 Kb6 Bg1 57 +50.00 191.6M 0:04.76 Bf2 Ke6 Kg2 Kd7 Bg1 Ke6 56 +50.00 159.9M 0:03.96 Bf2 Ke6 Kg2 Kd7 Bg1 Ke6 55 +50.00 139.7M 0:03.46 Bf2 Ke6 Kg2 Kd7 Bg1 Ke6 54 +50.00 122.1M 0:03.03 Bf2 Ke6 Kg2 Kd7 Bg1 Ke6 53 +50.00 105.2M 0:02.62 Bf2 Ke6 Kg2 Kd7 Bg1 Ke6 52 +50.00 88.6M 0:02.20 Bf2 Ke6 Kg2 Kd7 Bg1 Ke8 Kf2 Ke7 Ke2 Kd7 Kd2 Kc6 Bf2 Kc7 Be1 Kd7 Bf2 51 +50.00 72.3M 0:01.80 Bf2 Ke6 Kg2 Kd7 Bg1 Ke6 50 +50.00 61.1M 0:01.53 Bf2 Ke6 Kg2 Kd7 Bg1 Ke6 49 +50.00 53.5M 0:01.34 Bf2 Ke6 Kg2 Kd7 Bg1 Ke6 48 +50.00 39.0M 0:00.99 Bf2 Ke6 Kg2 Kd7 Bg1 Ke6 47 +50.00 31.8M 0:00.81 Bf2 Ke6 Kg2 Kd7 Bg1 Ke6 46 +50.00 23.7M 0:00.60 Bf2 Ke6 Kg2 Kd7 Bg1 Ke6 45 +50.00 17.8M 0:00.45 Bf2 Ke6 Kg2 Kd7 Bg1 Ke6 44 +50.00 15.1M 0:00.38 Bf2 Ke6 Kg2 Kd7 Bg1 Ke6 43 +50.00 12.6M 0:00.32 Bf2 Ke6 Kg2 Kd7 Bg1 Ke6 42 +50.00 10.5M 0:00.27 Bf2 Ke6 Kg2 Kd7 Bg1 Ke6 41 +50.00 8.68M 0:00.22 Bf2 Ke6 Kg2 Kd7 Bg1 Ke6 40 +50.00 7.54M 0:00.19 Bf2 Ke6 Kg2 Kd7 Bg1 Ke6 39 +50.00 5.17M 0:00.14 Bf2 Ke6 Kg2 Kd7 Bg1 Ke6 38 +50.00 4.16M 0:00.11 Bf2 Ke6 Kg2 Kd7 Bg1 Ke6 37 +50.00 3.36M 0:00.09 Bf2 Ke6 Kg2 Kd7 Bg1 Ke6 36 +50.00 2.47M 0:00.07 Bf2 Ke6 Kg2 Kd7 Bg1 Ke6 35 +50.00 2.00M 0:00.06 Bf2 Ke6 Kg2 Kd7 Bg1 Ke6 34 +50.00 1.80M 0:00.05 Bf2 Ke6 Kg2 Kd7 Bg1 Ke6 33 +50.00 1.44M 0:00.04 Bf2 Ke6 Kg2 Kd7 Bg1 Ke6 32 +50.00 1.13M 0:00.03 Bf2 Ke6 Kg2 Kd7 Bg1 Ke6 31 +50.00 838638 0:00.02 Bf2 Ke6 Kg2 Kd7 Bg1 Ke6 30 +50.00 641960 0:00.02 Bf2 Ke6 Kg2 Kd7 Bg1 Ke6 29 +50.00 553002 0:00.02 Bf2 Ke6 Kg2 Kd7 Bg1 Ke6 28 +50.00 474090 0:00.02 Bf2 Ke6 Kg2 Kd7 Bg1 Ke6 27 +50.00 360224 0:00.01 Bf2 Ke6 Kg2 Kd7 Bg1 Ke6 26 +50.00 309896 0:00.01 Bf2 Ke6 Kg2 Kd7 Bg1 Ke6 25 +50.00 298094 0:00.01 Bf2 Ke6 Kg2 Kd7 Bg1 Ke6 24 +50.00 270102 0:00.01 Bf2 Ke6 Kg2 Kd7 Bg1 Ke6 23 +50.00 230474 0:00.01 Bf2 Ke6 Kg2 Kd7 Bg1 Ke6 22 +50.00 189380 0:00.01 Bf2 Ke6 Kg2 Ke7 21 +50.00 162240 0:00.01 Bf2 Ke6 Kg2 Kd7 Bg1 Ke6 20 +50.00 154038 0:00.01 Bf2 Ke6 Kg2 Kd7 Bg1 Ke6 19 +50.00 141144 0:00.01 Bf2 Ke6 Kg2 Ke7 18 +50.00 126535 0:00.01 Bf2 Ke6 Kg2 Ke7 17 +50.00 113448 0:00.01 Bf2 Ke6 Kg2 Ke7 16 +50.00 100209 0:00.00 Bf2 Ke6 Kg2 Ke7 15 +50.00 90995 0:00.00 Bf2 Ke6 Kg2 Ke7 14 +50.00 86009 0:00.00 Bf2 Ke6 Kg2 Ke7 13 +50.00 82581 0:00.00 Bf2 Ke6 Kg2 Ke7 12 +50.00 78032 0:00.00 Bf2 Ke6 Kg2 Ke7 11 +50.00 75022 0:00.00 Bf2 Ke6 Kg2 Ke7 10 +50.00 71756 0:00.00 Bf2 Ke6 Kg2 Kd6 Bg1 Kd7 Kf2 Ke7 Ke2 Ke6 9 +50.00 69751 0:00.00 Bf2 Ke6 Kg2 Kd6 Bg1 Kd7 Kf2 Ke7 Ke2 8 +50.00 67865 0:00.00 Bf2 Ke6 Kg2 Kd6 Bg1 Kd7 Kf2 Ke7 7 +72.70 17685 0:00.00 Bf2 Kf6 Be1 Ke6 Kh2 Ke7 Kg2 6 +72.07 12308 0:00.00 Bf2 Kf6 Kh2 Kf7 Kg2 5 +70.93 5884 0:00.00 Bf2 Kf6 Kh2 Ke6 Kg2 4 +71.30 4605 0:00.00 Bf2 Kf6 Kh2 3 +71.27 3097 0:00.00 Kg2 Ke6 Bf2 2 +70.83 1898 0:00.00 Kg2 Kf6 1 +72.70 338 0:00.00 Kg2 1 Found 1511 tablebases 0 #
is Honey-XR7-FD out or released soon?