CCRL Discussion Board

... 'posts where cetrain endgame tablebase generators say ...' Do you have any specific, accurate references to these? What generators are out there, not including - please - the overly-inscrutable 'Skipper_NORTON'. I take it they do not include Nalimov, not geared for multi-core, FEG (ditto), Kono...

It scans the directory tree where the tables are being saved. After finding the first missing table it creates an empty file there (to stop other instances from solving the same table) and starts crunching. When the table is completed, it is saved instead of that empty file. There are a few more de...

It scans the directory tree where the tables are being saved. After finding the first missing table it creates an empty file there (to stop other instances from solving the same table) and starts crunching. When the table is completed, it is saved instead of that empty file. There are a few more de...

Although, I'd be still tempted to try slicing to improve it even further. Maybe if you saw the code for using a large buffer without having to deal with RAM slices, you might be tempted to make it work the way I did :) Do you think that something similar to your "locality of reference" im...

I've seen posts where certain endgame tablebase generators have options such as "-2" to take advantage of systems with 2 cores, usually followed up shortly by a request for "when is your -4 version going to become available?" I started thinking about a generalized approach to min...

What is the magic incantation to download it. The download does not work for me. Hi Dan, I uploaded it to my site. Link is: http://www.liquidnitrogenoverclocking.com/chess.zip It's about 38 MB compressed because it comes with up to tb4 pre-solved. I ran the 5-piece generator on my computer, it took...

Interesting! I'm now curious how the performance of your solver scales with additional RAM vs increased CPU speed, using the same reference storage. Have you done any such benchmarks with some larger tables? I've benchmarked just about every permutation of solving that I could think of :) I first b...

I do the same in my recent solvers - only legal positions are stored, in fact only unique legal positions. Kirill, Have you come up with a generalized indexing function for all material distribution permutations? I can do it for all endgames except those with en passant captures. That throws a monk...

Maybe I should rephrase:

Marc emailed me the position and the moves, and asked if I would link it into one of my javascript pages on the Gothic Chess site, and I said "Sure, no problem."

Ed: I think you are beginning to sound like an overclocking/fridge salesman rather than an endgame enthusiast - so maybe this is the wrong place for this duscussion. I'll leave that remark alone in the interest of peace. I noticed that your checkers benchmarks are on 6-man checkers endgames - but 9...

There seems little point in investing in cutting-edge processors to generate EGTs when the activity is essentially I/O limited. Hello Guy, My experiments in hardware have shown that alleviating the CPU-bound bottleneck in the Gulftown allows for that amazing architecture to really kick in. Overcloc...

If you have what it takes ED why not try creating a GUI to manipulate GAVIOTA EGTBs & by manipulating I mean generate, check, compress & even some FEN probing Well heck that covers just about everything now, doesn't it :) I did do some endgame database work with Marc Bourzutschky on the gam...

redpawn wrote:
The probing interface seems bad

In fact it's almost user hostile

Sometimes the smartest programmers make the worst graphical user interfaces

Maybe if they publish the format and the accessing code, someone can create a decent gui for it.

Mark showed me this ending way back in 2006.

http://www.gothicchess.com/endings/ches ... n/game.htm

It's a 517 move conversion.

That means 7-man should take about 1 month/ending. No, much faster than that. The tb5 speed was on a 3.9 GHz system, not parallelized. The 7-piece was being spec'd on a system with 12 processors, 24 threads, each at 5.0 GHz, and would take about 91 months. There's a great deal more than 91 endings ...

OK, now I see that you are not just starting with a lost position and taking the moves back one at a time. :-) Thanks for the explanation! I am using both a forward move generator and a reverse move generator. That way, I can determine wins, losses, and draws on any given pass, provided there is en...

BTW, are you slicing based on leading/trailing checker rank, or with some more fine slicing, like using the exact placement of all checkers as a slice? No, I do not have to subdivide my tablebases because of the buffering scheme I use. Here is a sample indexing function for 3 kings and 2 checkers v...

Thinking about hardware can be fun. Have you considered waiting 4 years before starting? Then you should be able to buy twice as fast hardware at half price and still finish 3.5 months earlier than if you buy now ;) The hardware I mentioned will not be available for more than 4 years. Consider this...

I'm not sure I follow here - in the usual retrograde analysis solving whenever you find a win, it's the shortest win for that position. When we are looking for wins in N we know that all wins in N-1 are already found and marked. What do you mean by "improving" the win? Is it something spe...

I just did some calculations based on: 1) The time it took to solve tb5 slices on my 3.9 GHz i7-860 2) The speed difference between that and a single 5.0 GHz i7-980X with 6 cores (12 threads) 3) The possible gains from parallelizing with a twin Gulftown setup (12 cores, 24 threads) Crunching all of ...

I could not get download to work, but from the posted documentation it seems to be a program for windows that is limited mainly by ram size and disk speed. I would not say "limited", I would say it makes better use of available RAM. I can tell as I watch it computing that it uses intellig...

Chess EndGame Analyzer. Generator of 3-4-5-6-7-chessman tablebases. http://generatorchess.com/ Format - DTM, 7-chessman tablebases can be generated using 4 GB of memory (maximum - 14 GB memory required). I started running the program on my 3.9 GHz i7-860 (see below) http://www.liquidnitrogenoverclo...

From the enclosed documentation" Retrospective_Chess_Generator, ChessDLL, RetroChess3 are 3 projects for chess game. The programs and dll require OS Windows. Retrospective_Chess_Generator is a 64-bit application, therefore it can work only in Windows 64-bit (e.g. Windows XP x64, Windows Vista x...

...endgames for checkers... Hi Ed, Did you have contacts with Jonathan Schaeffer, or is your work on the subject completely independent? Hi, Well, Jonathan was nice enough to mention me in his latest book, and on his website (see http://webdocs.cs.ualberta.ca/~chinook/thankyou/ ), but I did not wor...

OK, it's 40 moves then. I agree that ambiguously worded rules are potential sources of troubles. Can "progress" be defined similarly to chess as irreversible move (move of a checker, a capture, or a promotion)? Yes to both of those, and moving a checker forward or executing a capture rese...