Nordlandia wrote: ↑Wed Jul 31, 2019 7:04 am
What about generation time for 8-man for Lomonosov 2.
What about them?
I personally didn't see any great need for the 7-man bases to be created.
5-man tablebases are relatively small and most of the files were useful. i.e. in a 1,000,000 game database ~90% of the end games were seen at least once. Which means ~10% weren't seen at all. Another 30% of the files were seen at a rate of less than 1 games in 50,000. Not exactly what you would call “high use”. But since they only consume about 1GB of disk space this wasn't an issue. About 4.7% of all games include 5-man TB positions.
6-man tablebases are much larger at ~150Gb. Only about 40% of the endgames are seen at a rate greater than 1 game in 50,000. So about 90Gb of the files are essentially useless. About 6% of all games contain a 6-man TB position.
7-man tablebases are large enough that most people will have to make special accommodations to obtain and use them. Approximately 80% of these endgames are seen less than 1 game in 50,000 and ~54% are seen at less than 1 game in a million. These file are huge! I don't know what the total size is but I've counted of 18,000GB of files. That's quite a bit of data considering 80% (~14.4 TB) is of questionable value. i.e. it's a waste of disk space for most people's applications.
8-man seems like a waste for anything other than academic purposes or analysis. They would likely consume around 2PB of disk space. From a practical point of view, there are only a couple of these files that are worth the effort to generate. I did an analysis about 5-years ago and the data I have suggests that SOME of these files are worth generating.
Code: Select all
# endgame # occ. Sum # occ.
1 krppkrpp 128,688 128,688
2 krpppkrp 55,780 184,468
3 krpppkrp 55,780 240,248
4 kpppkppp 48,227 288,475
5 kbppkbpp 23,218 311,693
6 kbpppkbp 10,955 322,648
7 kppppkpp 10,235 332,883
8 kpppkbpp 8,543 341,426
9 krppkrbp 8,266 349,692
10 kpppknpp 6,829 356,521
11 krppkrnp 6,429 362,950
12 krbppkrp 5,987 368,937
13 kpppkrpp 5,442 374,379
14 krnppkrp 4,899 379,278
15 krpppkpp 4,155 383,433
16 krpppkpp 4,155 387,588
17 kbpppkpp 4,022 391,610
18 knpppkpp 3,588 395,198
19 kpppkqpp 3,472 398,670
20 krppkqrp 2,146 400,816
21 krppppkr 2,056 402,872
22 kqpppkpp 2,025 404,897
23 krrppkrp 1,805 406,702
24 krppkrrp 1,681 408,383
25 krpppkrb 1,597 409,980
26 krpppkrn 1,374 411,354
27 kbppknbp 1,244 412,598
28 kbppkrbp 1,025 413,623
Keep in mind that this was from a 7M game database so your mileage may vary. This wasn't taken from a complete analysis. It was data I already had on hand from a “first look” analysis. It would take a little more work to go back and verify these numbers and make sure the list is “relatively” complete as far as containing the endgames that will see the most occurrences in a give number of games. I would note that since the size of each file is unknown it's not possible to rank them in order of number of occurrences per MB of file.
These files are likely to be 100 times the size of the 7-man files so they aren't worth generating unless they have at large number of occurrences per 1M games. In this case, I listed those that occur with a frequency of at least 1 game in a 7000.
I think what is needed is a utility like Finalgen that uses 6-man (or 7-man since they are already generated) syzygy TBs as it's base and can generate given TB's to solve specific problems.
Finalgen has several huge advantages. It doesn't generate the whole TB at ones, just the pawn slices that correspond to the given problem, this makes it use much less RAM and, it has a GUI that anyone can uses to extend it's endgame table bases and query the data in the data set.
It does have several limitations though. It doesn't use any pre-generated TB's as a base set. It can only handle positions with kings and one non-pawn piece per side plus pawns. It's not multi-threaded, it's 32-bit, it doesn't use a “standard” GUI as it's interface, it has no ability to compress it's data, and there is no way to see what data is already in it's data set.
Something like Finalgen that uses SYZYGY as it's base set of EGTBs and can build on the base by adding more pawns as needed would be a very handy gadget. It would be orders of magnitude better than blindly generating the complete set of 8-man TBs!
Regards,
Zenmastur