Search found 92 matches

by koistinen
Sun Dec 17, 2023 10:33 pm
Forum: Endgame Tablebases
Topic: Chess engines can soon simulate tablebases for any number of pieces?
Replies: 2
Views: 30434

Re: Chess engines can soon simulate tablebases for any number of pieces?

To simulate any number of pieces, try limiting hash table size and see how engines handle a small number of pieces. The ones it gets wrong when searching for a few minutes, try searching a few hours and see how often that fixes the problem. I think it won't work for all positions, but seeing how oft...
by koistinen
Sun Apr 09, 2023 7:37 pm
Forum: Endgame Tablebases
Topic: New attempt at 8-man and beyond
Replies: 6
Views: 55857

Re: New attempt at 8-man and beyond

Here is my plan to make the problem easier so someone with my ability might solve it: Initial limitation: Only compute white wins as it simplifies the code a little. Also don't worry about pawns. Make a naïve implementation including code working for array. Save result. Write query code for files. I...
by koistinen
Sat Jan 28, 2023 9:35 pm
Forum: Endgame Tablebases
Topic: Duck Chess
Replies: 3
Views: 10628

Re: Duck Chess

Sounds like there might be some fun optimizations there, esp. with the 2 duck positions idea.
by koistinen
Sat Jan 28, 2023 8:51 am
Forum: Endgame Tablebases
Topic: New attempt at 8-man and beyond
Replies: 6
Views: 55857

Re: New attempt at 8-man and beyond

I hope you meant "no trouble" or "little trouble". An ominous indication of the complexity of your scheme. No, I mean to make the problem easier, so someone like myself, who has trouble juggling all the details, is able to do it. One part of it is applying the good advice I got ...
by koistinen
Thu Dec 22, 2022 8:53 pm
Forum: Endgame Tablebases
Topic: New attempt at 8-man and beyond
Replies: 6
Views: 55857

Re: New attempt at 8-man and beyond

After 18 months of failing I have decided I am not as good at programming as I thought. Next step is writing a plan for solving the problem for someone who has trouble juggling all the details required for the solution I have in mind. First part of it will be a very naïve way of doing the computatio...
by koistinen
Thu Oct 06, 2022 8:08 pm
Forum: Endgame Tablebases
Topic: How hard would it be to implement Tetris pieces into chess endgame tablebases?
Replies: 6
Views: 12891

Re: How hard would it be to implement Tetris pieces into chess endgame tablebases?

Or, if the L is allowed is allowed to rotate, 4 times as many, as its orientation also becomes part of the game state. Or yet another factor 2 more if it is also allowed to flip over to a mirro image. Actually, the rotations and mirrorings would be cancelled out exactly by being able to rotate and ...
by koistinen
Tue Oct 04, 2022 12:12 pm
Forum: Endgame Tablebases
Topic: How hard would it be to implement Tetris pieces into chess endgame tablebases?
Replies: 6
Views: 12891

Re: How hard would it be to implement Tetris pieces into chess endgame tablebases?

Treating it as one piece seems reasonalble. Would it have to stay on the board in its entirety? Would it be allowed to capture even if no capture of itself was allowed? Would it be allowed to rotate, and if so, when and around what axis? Have you tried playing with it on a chess board to see what ca...
by koistinen
Sun Oct 02, 2022 9:27 pm
Forum: Endgame Tablebases
Topic: How hard would it be to implement Tetris pieces into chess endgame tablebases?
Replies: 6
Views: 12891

Re: How hard would it be to implement Tetris pieces into chess endgame tablebases?

Try defining the rules for your new piece. Then play with it and you should be able to see if you want a tablebase. Fantasy pieces are generally not hard to implement a tablebase for. If you have a queen which can lay eggs, the number of eggs need to be limited in order for a tablebase to be practic...
by koistinen
Sat Jun 19, 2021 1:14 pm
Forum: Endgame Tablebases
Topic: New attempt at 8-man and beyond
Replies: 6
Views: 55857

Re: New attempt at 8-man and beyond

Is the idea that interleaving bits from white and black pieces in the index improves data access locality, reducing memory requirements? Or is the indexing geared towards applying 8-way symmetry through simple bitwise operators, thereby improving calculating speed? (Or both.) Yes, the idea is to im...
by koistinen
Tue Jun 15, 2021 6:56 pm
Forum: Endgame Tablebases
Topic: New attempt at 8-man and beyond
Replies: 6
Views: 55857

New attempt at 8-man and beyond

I got some good advice here which I didn't take, but now I am trying to do better. To do so I am starting with writing a design document: https://github.com/Koistinen/Endgame/blob/master/algo.txt The goal is to avoid optimizing much except what is needed to fit in ram. In the beginning extra disk i/...
by koistinen
Thu May 27, 2021 1:06 pm
Forum: Endgame Tablebases
Topic: 8-man tablebases already exist?
Replies: 4
Views: 40026

Re: 8-man tablebases already exist?

I think Google, Facebook, et.c. have shown us that centrally controlled computing easily turns becomes evil. That is why I prefer decentralized computing, not just distributed. That way I don't get to lord it over people. Besides computer chess I have also been interested in crypto techniques for qu...
by koistinen
Sun May 23, 2021 5:58 pm
Forum: Endgame Tablebases
Topic: 8-man tablebases already exist?
Replies: 4
Views: 40026

Re: 8-man tablebases already exist?

I've been thinking of how to do 8-man and beyond and a decentralized way of computing it seems interesting as storage is one of the biggest problems. For 8-man each pawnless endgame table need only take 2-3 months (with 50 move rule, proportional with dtc and worse for dtm) given each computing part...
by koistinen
Tue Jun 09, 2015 9:26 am
Forum: Endgame Tablebases
Topic: 7-piece syzygy
Replies: 5
Views: 52006

Re: 7-piece syzygy

How about this answer: When computers have 64 times as much ram, i.e. 64*16 GB = 1 TB of ram. So, perhaps in 12 years assuming doubling every 2 years?
by koistinen
Tue Apr 23, 2013 12:27 pm
Forum: Endgame Tablebases
Topic: New 6-piece tablebase generator
Replies: 14
Views: 88918

Re: New 6-piece tablebase generator

Nice, C and GNU Licence!

Have downloaded and will study it.
by koistinen
Mon Jun 25, 2012 6:49 pm
Forum: Endgame Tablebases
Topic: Number of positions in chess endgames
Replies: 20
Views: 145692

Re: Number of positions in chess endgames

Unless I'm missing something, it should be 16 (4x4), because with this piece placement both white and black can have 4 different possibilities of castling rights. Ok, that is very reasonable, because it could get complicated if you had to consider if those rights might ever be used when counting. 4...
by koistinen
Mon Jun 25, 2012 1:17 am
Forum: Endgame Tablebases
Topic: Number of positions in chess endgames
Replies: 20
Views: 145692

Re: Number of positions in chess endgames

I like it! Metrics have many benefits. To clarify could you look at the position and explain?

rnb1kbnr/pppp1ppp/8/4p3/5PPq/8/PPPPP2P/RNBQKBNR w
rnb1kbnr/pppp1ppp/8/4p3/5PPq/8/PPPPP2P/RNBQKBNR w

How many ULPs have the pieces on the squares as above and why?
by koistinen
Fri Nov 18, 2011 5:21 am
Forum: Endgame Tablebases
Topic: fairygen 1.2 released
Replies: 13
Views: 19566

Re: fairygen 1.2 released

After changing line 802 to: for(tb=p;4095&(long)tb;) ++tb; /* align with cash line */ and including string.h it appears to compile without complaints from GCC on my Debian system. Running with argument "KQ.K" results in output: 2602010 2603000 # N: 18,3 14,3 -14,3 -18,3 33,3 31,3 -31,3...
by koistinen
Sun Jun 12, 2011 2:21 pm
Forum: Endgame Tablebases
Topic: Generator of 3-4-5-6-7-chessman tablebases. Version 4.
Replies: 22
Views: 41741

Re: Generator of 3-4-5-6-7-chessman tablebases. Version 4.

petter wrote:How long do you think it may take to calculate one of the 7 chessmen tablebases in a i-950 home computer with
6 gigabyte of ram?
My estimation is: at least 4000 times the time it takes to calculate a 5-man or 60 times the time it takes to calculate a 6-man.
by koistinen
Fri Jun 03, 2011 9:11 pm
Forum: Endgame Tablebases
Topic: Generator of 3-4-5-6-7-chessman tablebases. Version 4.
Replies: 22
Views: 41741

Re: Generator of 3-4-5-6-7-chessman tablebases. Version 4.

Has anyone got performance data for this generator?
Say, how long does it take to generate all 5-man tablebases? On what computer? What metric?
by koistinen
Wed Apr 27, 2011 1:31 pm
Forum: Endgame Tablebases
Topic: 7-man EGTB Bounty Reborn - General Discussion
Replies: 11
Views: 24251

Re: 7-man EGTB Bounty Reborn - General Discussion

I'd be willing to put this speed into bounty specs (relaxed a bit for safety). Assuming there is no other choice. If there is other choice, then I'd try to aim for a faster-performing generator. What is the performance of the currently available 6-man generators on current hardware when the table f...
by koistinen
Thu Apr 21, 2011 12:02 pm
Forum: Endgame Tablebases
Topic: 7-man EGTB Bounty Reborn - General Discussion
Replies: 11
Views: 24251

Re: 7-man EGTB Bounty Reborn - General Discussion

I think it would be nice if the demand for speed is lax as it is much easier to implement something when you are allowed to be half as fast as optimum, and more laxity gives more ease. In my scheme, there is one 46.4 GiBy table that needs to be read twice and written once every iteration. With dupli...
by koistinen
Thu Apr 21, 2011 5:49 am
Forum: Endgame Tablebases
Topic: 7-man EGTB Bounty Reborn - Infrastructure Discussion
Replies: 1
Views: 7073

Re: 7-man EGTB Bounty Reborn - Infrastructure Discussion

Distributed probing should be fun. One way for a server to prove to a client that an honest answer with hash function F constructed using cryptographic hash function H is this: F(T)-> if small_enough(T)->H(T); else H([H(first_half(T)),H(second_half(T))]). Client must know F(Table). Server has a tabl...
by koistinen
Tue Apr 19, 2011 9:11 pm
Forum: Endgame Tablebases
Topic: 7-man EGTB Bounty Reborn - General Discussion
Replies: 11
Views: 24251

Re: 7-men EGTB Bounty Reborn - General Discussion

A comment on 7-men EGTB Bounty Reborn - Summary . While requiring that probing code be available in C is sensible, having programming language requirements for the generator might be harmful. Allow any language as long as there are no dependencies on nonfree code. Readability requirements are fine, ...
by koistinen
Tue Apr 19, 2011 8:10 pm
Forum: Endgame Tablebases
Topic: 7-man EGTB Bounty Reborn - Metric Discussion
Replies: 20
Views: 29349

Re: 7-men EGTB Bounty Reborn - Metric Discussion

With an the clean code and OSI approved license requirements it seems likely that those who want a different metric would be able to adapt the code to their needs. I'd like to see any of the metrics WDL50-DTM be allowed. (That is: any one of the metrics mentioned in this thread if computed should co...
by koistinen
Tue Apr 19, 2011 7:42 pm
Forum: Endgame Tablebases
Topic: 7-man EGTB Bounty Reborn - General Discussion
Replies: 11
Views: 24251

Re: 7-men EGTB Bounty Reborn - General Discussion

Maybe specify a benchmark computer exactly would be good, what processor, motherboard, memory and disks are connected. Because 4 GB(gigabytes) memory modules now are reasonably priced, allowing a requirement of 24 GB at 10-20 GB/s for generating computer should be ok. (I would not need more than 8GB...