Author: Robert Hyatt
Date: 10:23:29 09/06/01
Go up one level in this thread
On September 06, 2001 at 13:17:52, Robert Hyatt wrote:
>On September 06, 2001 at 12:02:52, Peter Fendrich wrote:
>
>>On September 06, 2001 at 10:21:40, Robert Hyatt wrote:
>>
>>>On September 06, 2001 at 06:12:16, Odd Gunnar Malin wrote:
>>>
>>>>>
>>>>I was pondering with this strange results from Tiger and Wilhelm and (and my
>>>>engine :) ).
>>>>
>>>>There is other possibilities for long search time (many nodes) before the score
>>>>change. If you don't save hash when depth=0, eg. after returning from qsearch
>>>>you get such results ( I don't save hash in qsearch).
>>>>
>>>>From my engine: (score change from 140 to 226)
>>>>hash save when depth=0 -> 430k nodes
>>>>no hashing when depth=0 -> 8731k nodes
>>>>
>>>>Odd Gunnar Malin
>>>
>>>
>>>I don't hash in the q-search either. However, fine70 runs better with poor
>>>move ordering, due to hash grafting. If you search the best move first at
>>>every node, this takes 26 plies to solve, IIRC. If your move ordering is
>>>less than optimal, you require fewer plies to find the correct move (Kb1).
>>>
>>>At ply 26, you should see winning another pawn, for a score of +2 plus whatever
>>>positional edge you assign for creating a passed pawn. In a few more plies
>>>the score should jump yet again... and again...
>>
>>At ply 25, mine (Terra) jumps up to +3,4. Does that mean less optimal move
>>ordering? How do you know?
>>Couldn't it be at some point better move ordering?
>>//Peter
>
>No. I know it because the solution is 26 plies, minimum. The only way to
>solve this with fewer than 26 plies is through hash grafting. Works like this:
>
>You first search the right move at ply 1, but you search a poor move at
>ply 2, and reach a position where you can force the win of a pawn.
>
>Then you search the right move at ply 2, but discover that you can force the
>game to a position you encountered in the first search, where you forced a win
>after weak defense. You use this hash information to prove that a position
>is won, even though you really can't search deeply enough to see the win. If
>you search best-first every time, this can't possibly happen, and it will take
>26 plies.
>
>It has been a known issue for years, and is why programs solve this anywhere
>between 16 plies and 26. And it is why, if you change the hash size, you
>will likely change the depth you solve it. In fact, it is pretty common to
>increase the hash size and increase the depth required to find the Kb1 move,
>because hash moves improve move ordering...
>
>A real pain, of course. :)
By the way, here is my output for a small hash, just for
fun, and to show that my move ordering is not that good either. :)
This is using one processor, default hash size, 700mhz PIII.
small hash:
time surplus 0.00 time limit 30.00 (3:30)
nss depth time score variation (1)
1 0.00 1.21 1. Kb2
1-> 0.00 1.21 1. Kb2
2 0.00 1.01 1. Kb2 Kb6
2-> 0.00 1.01 1. Kb2 Kb6
3 0.00 1.21 1. Kb2 Kb6 2. Kc3
3-> 0.00 1.21 1. Kb2 Kb6 2. Kc3
4 0.00 1.21 1. Kb2 Kb6 2. Kc3 Kc7
4-> 0.00 1.21 1. Kb2 Kb6 2. Kc3 Kc7
5 0.00 1.41 1. Kb2 Kb6 2. Kc3 Kc7 3. Kc4
5-> 0.00 1.41 1. Kb2 Kb6 2. Kc3 Kc7 3. Kc4
6 0.00 1.31 1. Kb2 Kb6 2. Kc3 Kc7 3. Kc4 Kd7
6-> 0.00 1.31 1. Kb2 Kb6 2. Kc3 Kc7 3. Kc4 Kd7
7 0.00 1.31 1. Kb2 Kb6 2. Kc3 Kc7 3. Kd3 Kd7 4.
Kc4
7-> 0.00 1.31 1. Kb2 Kb6 2. Kc3 Kc7 3. Kd3 Kd7 4.
Kc4
8 0.00 1.31 1. Kb2 Kb6 2. Kc3 Kc7 3. Kd3 Kd7 4.
Kc4 Ke7
8-> 0.00 1.31 1. Kb2 Kb6 2. Kc3 Kc7 3. Kd3 Kd7 4.
Kc4 Ke7
9 0.01 1.41 1. Kb2 Kb6 2. Kc3 Kc7 3. Kc4 Kb6 4.
Kd3 Kc7 5. Kc4
9-> 0.01 1.41 1. Kb2 Kb6 2. Kc3 Kc7 3. Kc4 Kb6 4.
Kd3 Kc7 5. Kc4
10 0.01 1.21 1. Kb2 Kb8 2. Kc2 Kc8 3. Kd3 Kc7 4.
Kc4 Kb6 5. Kd3 Kc7 <HT>
10-> 0.01 1.21 1. Kb2 Kb8 2. Kc2 Kc8 3. Kd3 Kc7 4.
Kc4 Kb6 5. Kd3 Kc7 <HT>
11 0.01 1.21 1. Kb2 Kb8 2. Kc2 Kc8 3. Kd3 Kc7 4.
Kc4 Kb6 <HT>
11-> 0.01 1.21 1. Kb2 Kb8 2. Kc2 Kc8 3. Kd3 Kc7 4.
Kc4 Kb6 <HT>
12 0.01 1.21 1. Kb2 Kb8 2. Kc2 Kc8 3. Kd3 Kc7 4.
Kc4 Kb6 5. Kc3 Kb7 6. Kc4 Kb6 <HT>
12-> 0.01 1.21 1. Kb2 Kb8 2. Kc2 Kc8 3. Kd3 Kc7 4.
Kc4 Kb6 5. Kc3 Kb7 6. Kc4 Kb6 <HT>
13 0.02 1.21 1. Kb2 Kb8 2. Kc2 Kc8 3. Kd3 Kc7 4.
Kc4 Kb6 5. Kc3 Kb7 6. Kc4 Kb6 <HT>
13-> 0.02 1.21 1. Kb2 Kb8 2. Kc2 Kc8 3. Kd3 Kc7 4.
Kc4 Kb6 5. Kc3 Kb7 6. Kc4 Kb6 <HT>
14 0.02 1.21 1. Kb2 Kb8 2. Kc2 Kc8 3. Kd3 Kc7 4.
Kc4 Kb6 5. Kc3 Kb7 6. Kc4 Kb6 <HT>
14-> 0.02 1.21 1. Kb2 Kb8 2. Kc2 Kc8 3. Kd3 Kc7 4.
Kc4 Kb6 5. Kc3 Kb7 6. Kc4 Kb6 <HT>
15 0.02 1.21 1. Kb2 Kb8 2. Kc2 Kc8 3. Kd3 Kc7 4.
Kc4 Kb6 5. Kc3 Kb7 6. Kc4 Kb6 <HT>
15-> 0.02 1.21 1. Kb2 Kb8 2. Kc2 Kc8 3. Kd3 Kc7 4.
Kc4 Kb6 5. Kc3 Kb7 6. Kc4 Kb6 <HT>
16 0.02 1.21 1. Kb2 Kb8 2. Kc2 Kc8 3. Kd3 Kc7 4.
Kc4 Kb6 5. Kb3 Kc7 6. Kc3 Kb7 7. Kd2
Kc8 8. Ke3 Kd7
16-> 0.02 1.21 1. Kb2 Kb8 2. Kc2 Kc8 3. Kd3 Kc7 4.
Kc4 Kb6 5. Kb3 Kc7 6. Kc3 Kb7 7. Kd2
Kc8 8. Ke3 Kd7
17 0.03 1.21 1. Kb2 Kb8 2. Kc2 Kc8 3. Kd3 Kc7 4.
Kc4 Kb6 5. Kb3 Kc7 6. Kc3 Kb7 7. Kd2
Kc8 8. Ke3 Kd7 9. Kd3
17-> 0.03 1.21 1. Kb2 Kb8 2. Kc2 Kc8 3. Kd3 Kc7 4.
Kc4 Kb6 5. Kb3 Kc7 6. Kc3 Kb7 7. Kd2
Kc8 8. Ke3 Kd7 9. Kd3
18 0.04 1.21 1. Kb2 Ka8 2. Kc3 Kb7 3. Kd2 Kc8 4.
Ke2 Kd7 5. Ke3 Kd8 6. Kf3 Ke7 7. Kf2
Kf6 8. Ke2 Kg6 9. Kd3 Kf6
18 0.04 ++ 1. Kb1!!
(2) 18-> 0.05 1.60 1. Kb1
19 0.05 1.21 1. Kb1 Kb8 2. Kc1 Kb7 3. Kd2 Kc8 4.
Ke2 Kd7 5. Ke3 Kd8 6. Kf3 Ke7 7. Kf2
Kf6 8. Ke2 Kg6 9. Kf3 Kf6 <HT>
19-> 0.06 1.21 1. Kb1 Kb8 2. Kc1 Kb7 3. Kd2 Kc8 4.
Ke2 Kd7 5. Ke3 Kd8 6. Kf3 Ke7 7. Kf2
Kf6 8. Ke2 Kg6 9. Kf3 Kf6 <HT>
20 0.06 ++ 1. Kb1!!
20 0.07 3.01 1. Kb1 Kb8 2. Kc2 Kb7 3. Kc3 Kc7 4.
Kd3 Kb6 5. Ke3 Kc7 6. Kf3 Kd7 7. Kg3
Ke7 8. Kh4 Kf6 9. Kh5 Kg7 10. Kg5 Kh8
20-> 0.07 3.01 1. Kb1 Kb8 2. Kc2 Kb7 3. Kc3 Kc7 4.
Kd3 Kb6 5. Ke3 Kc7 6. Kf3 Kd7 7. Kg3
Ke7 8. Kh4 Kf6 9. Kh5 Kg7 10. Kg5 Kh8
21 0.08 3.28 1. Kb1 Kb8 2. Kc2 Kb7 3. Kc3 Kc7 4.
Kd3 Kb6 5. Ke3 Kc7 6. Kf3 Kd7 7. Kg3
Ke7 8. Kh4 Kf6 9. Kh5 Ke7 10. Kg6 Kd7
11. Kxf5
21-> 0.08 3.28 1. Kb1 Kb8 2. Kc2 Kb7 3. Kc3 Kc7 4.
Kd3 Kb6 5. Ke3 Kc7 6. Kf3 Kd7 7. Kg3
Ke7 8. Kh4 Kf6 9. Kh5 Ke7 10. Kg6 Kd7
11. Kxf5
22 0.09 3.28 1. Kb1 Kb8 2. Kc2 Kb7 3. Kc3 Kc7 4.
Kd3 Kb6 5. Ke3 Kc7 6. Kf3 Kd7 7. Kg3
Ke7 8. Kh4 Kf6 9. Kh5 Ke7 10. Kg6 Kd7
11. Kxf5 Ke7
22-> 0.09 3.28 1. Kb1 Kb8 2. Kc2 Kb7 3. Kc3 Kc7 4.
Kd3 Kb6 5. Ke3 Kc7 6. Kf3 Kd7 7. Kg3
Ke7 8. Kh4 Kf6 9. Kh5 Ke7 10. Kg6 Kd7
11. Kxf5 Ke7
23 0.11 3.44 1. Kb1 Kb8 2. Kc2 Kb7 3. Kc3 Kc7 4.
Kd3 Kb6 5. Ke3 Kc7 6. Kf3 Kd7 7. Kg3
Ke7 8. Kh4 Kf6 9. Kh5 Ke7 10. Kg6 Kd7
11. Kxf5 Ke7 12. Ke4
23-> 0.11 3.44 1. Kb1 Kb8 2. Kc2 Kb7 3. Kc3 Kc7 4.
Kd3 Kb6 5. Ke3 Kc7 6. Kf3 Kd7 7. Kg3
Ke7 8. Kh4 Kf6 9. Kh5 Ke7 10. Kg6 Kd7
11. Kxf5 Ke7 12. Ke4
24 0.13 3.44 1. Kb1 Kb8 2. Kc2 Kb7 3. Kc3 Kc7 4.
Kd3 Kb6 5. Ke3 Kc7 6. Kf3 Kd7 7. Kg3
Ke7 8. Kh4 Kf6 9. Kh5 Ke7 10. Kg6 Kd7
11. Kxf5 Ke7 12. Ke4 Kd7
24-> 0.13 3.44 1. Kb1 Kb8 2. Kc2 Kb7 3. Kc3 Kc7 4.
Kd3 Kb6 5. Ke3 Kc7 6. Kf3 Kd7 7. Kg3
Ke7 8. Kh4 Kf6 9. Kh5 Ke7 10. Kg6 Kd7
11. Kxf5 Ke7 12. Ke4 Kd7
25 0.16 3.47 1. Kb1 Kb8 2. Kc2 Kb7 3. Kc3 Kc7 4.
Kd3 Kb6 5. Ke3 Kc7 6. Kf3 Kd7 7. Kg3
Ke7 8. Kh4 Kf6 9. Kh5 Ke7 10. Kg6 Kd7
11. Kxf5 Ke7 12. Kg5 Kd7 13. f5
25-> 0.16 3.47 1. Kb1 Kb8 2. Kc2 Kb7 3. Kc3 Kc7 4.
Kd3 Kb6 5. Ke3 Kc7 6. Kf3 Kd7 7. Kg3
Ke7 8. Kh4 Kf6 9. Kh5 Ke7 10. Kg6 Kd7
11. Kxf5 Ke7 12. Kg5 Kd7 13. f5
26 0.19 3.47 1. Kb1 Kb8 2. Kc2 Kb7 3. Kc3 Kc7 4.
Kd3 Kb6 5. Ke3 Kc7 6. Kf3 Kd7 7. Kg3
Ke7 8. Kh4 Kf6 9. Kh5 Ke7 10. Kg6 Kd7
11. Kxf5 Ke7 12. Kg5 Kd8 13. f5 Kd7
26-> 0.20 3.47 1. Kb1 Kb8 2. Kc2 Kb7 3. Kc3 Kc7 4.
Kd3 Kb6 5. Ke3 Kc7 6. Kf3 Kd7 7. Kg3
Ke7 8. Kh4 Kf6 9. Kh5 Ke7 10. Kg6 Kd7
11. Kxf5 Ke7 12. Kg5 Kd8 13. f5 Kd7
27 0.39 3.75 1. Kb1 Kb8 2. Kc2 Kb7 3. Kc3 Kc7 4.
Kd3 Kb6 5. Ke3 Kc7 6. Kf3 Kd7 7. Kg3
Ke7 8. Kh4 Kf6 9. Kh5 Ke7 10. Kg6 Ke8
11. Kxf5 Kf7 12. Kg5 Kg7 13. f5 Kf7
14. Kf4
27-> 0.39 3.75 1. Kb1 Kb8 2. Kc2 Kb7 3. Kc3 Kc7 4.
Kd3 Kb6 5. Ke3 Kc7 6. Kf3 Kd7 7. Kg3
Ke7 8. Kh4 Kf6 9. Kh5 Ke7 10. Kg6 Ke8
11. Kxf5 Kf7 12. Kg5 Kg7 13. f5 Kf7
14. Kf4
28 0.44 3.75 1. Kb1 Kb8 2. Kc2 Kb7 3. Kc3 Kc7 4.
Kd3 Kb6 5. Ke3 Kc7 6. Kf3 Kd7 7. Kg3
Ke7 8. Kh4 Kf6 9. Kh5 Ke7 10. Kg6 Ke8
11. Kf6 Kd8 12. Kxf5 Kd7 13. Ke4 Kd8
14. f5 Kd7
28-> 0.44 3.75 1. Kb1 Kb8 2. Kc2 Kb7 3. Kc3 Kc7 4.
Kd3 Kb6 5. Ke3 Kc7 6. Kf3 Kd7 7. Kg3
Ke7 8. Kh4 Kf6 9. Kh5 Ke7 10. Kg6 Ke8
11. Kf6 Kd8 12. Kxf5 Kd7 13. Ke4 Kd8
14. f5 Kd7
29 0.64 ++ 1. Kb1!!
29 3.43 4.28 1. Kb1 Kb8 2. Kc2 Kb7 3. Kc3 Kc7 4.
Kd3 Kb6 5. Ke3 Kc7 6. Kf3 Kd7 7. Kg3
Kd8 8. Kh4 Kd7 9. Kg5 Ke7 10. Kxf5
Kf7 11. Kg5 Kg7 12. f5 Kf7 13. f6 Kf8
14. Kf5 <HT>
29-> 3.43 4.28 1. Kb1 Kb8 2. Kc2 Kb7 3. Kc3 Kc7 4.
Kd3 Kb6 5. Ke3 Kc7 6. Kf3 Kd7 7. Kg3
Kd8 8. Kh4 Kd7 9. Kg5 Ke7 10. Kxf5
Kf7 11. Kg5 Kg7 12. f5 Kf7 13. f6 Kf8
14. Kf5 <HT>
30 3.97 4.61 1. Kb1 Kb8 2. Kc2 Kb7 3. Kc3 Kc7 4.
Kd3 Kb6 5. Ke3 Kc7 6. Kf3 Kd7 7. Kg3
Kd8 8. Kh4 Kd7 9. Kg5 Ke7 10. Kxf5
Kf7 11. Kg5 Kg7 12. f5 Kf7 13. f6 Kf8
14. Kg6 Kg8 15. f7+ Kf8 16. Kf6
30-> 3.99 4.61 1. Kb1 Kb8 2. Kc2 Kb7 3. Kc3 Kc7 4.
Kd3 Kb6 5. Ke3 Kc7 6. Kf3 Kd7 7. Kg3
Kd8 8. Kh4 Kd7 9. Kg5 Ke7 10. Kxf5
Kf7 11. Kg5 Kg7 12. f5 Kf7 13. f6 Kf8
14. Kg6 Kg8 15. f7+ Kf8 16. Kf6
31 4.18 -- 1. Kb1
31 4.60 4.80 1. Kb1 Kb8 2. Kc2 Kb7 3. Kc3 Kc7 4.
Kd3 Kb6 5. Ke3 Kc7 6. Kf3 Kd7 7. Kg3
Ke7 8. Kh4 Kf6 9. Kh5 Ke7 10. Kg6 <HT>
31-> 4.60 4.80 1. Kb1 Kb8 2. Kc2 Kb7 3. Kc3 Kc7 4.
Kd3 Kb6 5. Ke3 Kc7 6. Kf3 Kd7 7. Kg3
Ke7 8. Kh4 Kf6 9. Kh5 Ke7 10. Kg6 <HT>
32 4.95 4.80 1. Kb1 Kb8 2. Kc2 Kb7 3. Kc3 Kc7 4.
Kd3 Kb6 5. Ke3 Kc7 6. Kf3 Kd7 7. Kg3
Ke7 8. Kh4 Kf6 9. Kh5 Kf7 10. Kg5 Ke7
11. Kxf5 <HT>
32-> 4.95 4.80 1. Kb1 Kb8 2. Kc2 Kb7 3. Kc3 Kc7 4.
Kd3 Kb6 5. Ke3 Kc7 6. Kf3 Kd7 7. Kg3
Ke7 8. Kh4 Kf6 9. Kh5 Kf7 10. Kg5 Ke7
11. Kxf5 <HT>
33 5.39 4.80 1. Kb1 Kb8 2. Kc2 Kb7 3. Kc3 Kc7 4.
Kd3 Kb6 5. Ke3 Kc7 6. Kf3 Kd7 7. Kg3
Ke7 8. Kh4 Kf6 9. Kh5 Kf7 10. Kg5 Ke7
11. Kxf5 <HT>
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