Author: Eric Oldre
Date: 12:50:56 07/11/04
Go up one level in this thread
On July 11, 2004 at 15:21:07, Will Singleton wrote:
>On July 11, 2004 at 14:35:50, Eric Oldre wrote:
>
>>[D]8/k7/3p4/p2P1p2/P2P1P2/8/8/K7 w - - 0 1
>>
>>I ran my engine on the fine 70 position above. which Anthony Cozzie recommended
>>to me last night as a good position to test for transposition table issues.
>>below is my new engines analysis of the position.
>>
>>(note, I'm not yet sure if I will call it "Murderhole2" or give it a completely
>>new name)
>>
>>Murderhole2 release WB2 25 MB:
>> 1 00:00 1.48 a1b1
>> 2 00:00 1.40 a1b1 a7a8
>> 3 00:00 1.45 a1b1 a7a8 b1c1
>> 4 00:00 1.40 a1b1 a7b8 b1c1 b8c8
>> 5 00:00 1.40 a1b1 a7b8 b1b2 b8c8 b2c1
>> 6 00:00 1.40 a1b1 a7b8 b1b2 b8b7 b2c1 b7c8
>> 7 00:00 1.40 a1b1 a7b8 b1b2 b8b7 b2b1 b7c8 b1c1
>> 8 00:00 1.40 a1b1 a7b8 b1b2 b8b7 b2b1 b7b8 b1c1 c8b8
>> 9 00:00 1.45 a1b2 a7a8 b2c1 a8b8 c1d2 b8c8 d2c2
>>10 00:00 1.40 a1b2 a7a8 b2c1 a8b8 c1d2 b8c8 d2c2 c8b7 c2c1 b7c8
>>11 00:00 1.45 a1a2 a7a6 a2b2 a6b6 b2c3 b6a7 c3d2 a7a8 d2c2 a8b8
>>12 00:00 1.42 a1a2 a7a6 a2b2 a6b6 b2c3 b6a7 c3d2 a7a8 d2c2 a8b8 c2d2 b8c8
>>13 00:00 1.47 a1b1 a7b7 b1c1 b7a8 c1d2 a8b8 d2e1 b8b7 e1f1 b7c8 f1g2
>>14 00:01 1.45 a1b1 a7b7 b1a1 b7c8 a1b2 c8b7 b2b3 b7c7 b3c4 c7b6 c4c3
>>15 00:02 1.47 a1a2 a7a8 a2b1 a8b8 b1a2 b8c8 a2a3 c8b8 a3b3 b8b7 b3b2
>>16 00:04 1.45 a1a2 a7b7 a2b2 b7c8 b2c3 c8b7 c3b2 b7c8 b2c3 c8b7 c3b2 b7c8
>>b2a1 c8c7 c1b1
>>17 00:08 1.48 a1b1 a7a8 b1c1 a8a7 c1d2 a7b6 d2e2 b6c7 e2f3 c7d8 f3e2
>>18 00:12 1.58 a1a2 a7a8 a2b2
>>19 00:35 1.60 a1b1 a7b8 b1c1 b8c8 c1c2 c8c7 c2d3 c7b6 d3e2 b6c7 e2e3 c7d8
>>e3d3 d8c7
>>20 01:12 1.62 a1b1 a7b7 b1c1 b7c7 c1b2 c7c8 b2c2 c8b7 a2b2 b8c8 b2c2 c8b7
>>a2b2 b8c8 b2c2 c8b8 a3b3 b8c7
>>21 03:51 1.62 a1b1 a7b7 b1c1 b7c7 c1b2 c7c8 b2a2 c8b8 a2a1 b8b7 a1b1 b7a7
>>b1c1 a7b7
>>
>>it does eventually at depth 19 decide on the correct answer of a1b1. however, it
>>looks like it is simply it trying to avoid the draw by repitition and counts
>>itself as ahead due to it's extra pawn. it doesn't get a crushing score at this
>>depth at all.
>>
>>at this point the eval function is simply static material and piece/square value
>>tables, i hope to add more advanced techniques this week.
>>
>>I'm looking for some advice in interpreting these results.
>>
>>a) did I just not let it search deep enough?
>>b) does the fact that it took 3:51 to reach depth 21 indictate a issue with my
>>tranposition table? it was running at 1,200,000 nodes/sec.
>
>Yes. As you probably know from running other programs on this, it should blow
>thru 21 ply in less than a second. Do you use two tables or one? Depth or
>always replace?
>
currently i'm using only 1 table, and always replace, thinking more carefully
that could very well be the cause of the issue, as the useful results may be
getting thrown away. I'll try and get a two table scheme in place to see if that
changes my results, or maybe switch to a replace if deeper scheme and see if
that alone will fix it. (eventually i'll move to a 2 table system either way)
I'll make sure to report back the results when i get some.
>>
>>if there is a issue with my transposition table, could it be due to not having
>>random enough keys? here is the code i'm using to generate the numbers.
>>
>>U64 rand64(){
>> U64 retval = 0;
>> retval = (retval <<15) | rand();
>> retval = (retval <<15) | rand();
>> retval = (retval <<15) | rand();
>> retval = (retval <<15) | rand();
>> retval = (retval <<15) | rand();
>> return retval;
>>};
This page took 0.01 seconds to execute
Last modified: Thu, 15 Apr 21 08:11:13 -0700
Current Computer Chess Club Forums at Talkchess. This site by Sean Mintz.