Syzygy+Bases

a compact six piece endgame database developed by Ronald de Man, published April 01, 2013, but not as [|April Fool]. Syzygy Bases consist of two sets of files, **WDL** files storing win/draw/loss information considering the fifty-move rule for access during search, and **DTZ** files with distance-to-zero information for access at the root. The generator is released under the GNU General Public License Version 2, the thread safe probing code is released without restrictions. As of February 2015, all 3-5 and most important 6-men Syzygy Bases are commercially available on 4 [|DVDs] by ChessBase as //Endgame Turbo 4// for their products Deep Fritz 14, Komodo Chess 8, Houdini 4 or ChessBase 12/13. || toc =File Sizes=
 * Home * Knowledge * Endgame Tablebases * Syzygy Bases**
 * [[image:Three_Planets_Dance_Over_La_Silla.jpg link="https://en.wikipedia.org/wiki/File:Three_Planets_Dance_Over_La_Silla.jpg"]] ||~  || **Syzygy Bases**,
 * Syzygy - Three Planets Dance Over [|La Silla] It’s a real treat for photographers and astronomers alike: our skies are currently witnessing a phenomenon known as a syzygy — when three [|celestial bodies] (or more) nearly align themselves in the sky. When celestial bodies have similar ecliptic [|longitude], this event is also known as a triple near-[|conjunction]. Of course, this is just a trick of perspective, but this doesn't make it any less spectacular. In this case, these bodies are three [|planets], and the only thing needed to enjoy the show is a clear view of the sky at sunset. Luckily, this is what happened for [|ESO] [|photo ambassador] [|Yuri Beletsky], who had the chance to spot this spectacular view from ESO's [|La Silla Observatory] in northern [|Chile] on Sunday May 26, 2013. Above the round domes of the [|telescopes], three of the planets in our [|Solar System] — [|Jupiter] (top), [|Venus] (lower left), and [|Mercury] (lower right) — were revealed aftersunset, engaged in their cosmic dance. An alignment like this happens only once every several years. The last one took place in May 2011, and the next one will not be until October 2015. This celestial triangle was at its best over the last week of May, but you may still be able to catch a glimpse of the three planets as they form ever-changing arrangements during their journey across the sky - source [|Three Planets Dance Over La Silla | ESO], [|Syzygy (astronomy) from Wikipedia] ||~  ||^   ||
 * ~ Men ||~  ||~ WDL ||~   ||~ DTZ ||
 * ~ 5 ||~  ||> 378 MiB ||~   ||> 561 MiB ||
 * ~ 6 ||~  ||> 68.3 GiB ||~   ||> 81.9 GiB ||

The additional use of [|Haswell's] BMI2 Parallel Bits Deposit (PDEP) and Parallel Bits Extract (PEXT) instructions, or their slower serial implementations, allows further size reduction.

Generation of 7-men tablebases would require about 1 TB of RAM. Generation time will be about 64 x per table, which means around 175 x time total. Ronald de Man isn't interested in creation of 7-men Syzygy.

=During the Search= During the search, with the WDL tables stored on [|SSD], it is possible to probe the tables at all depths without much slowdown. They have been tested in Ronald de Man's engine Sjaak (playing on FICS as TrojanKnight(C)) a couple of months quite successfully, don't probing in quiescence search.

=At the Root= At the root, since pure DTZ50-optimal play (i.e. minimaxing the number of moves to the next capture or pawn move by either side) can be very unnatural, it might be desirable to let the engine search on the winning moves until it becomes clear that insufficient progress is being made and only then switch to DTZ-optimal play (e.g. by detecting repetitions and monitoring the halfmove clock).

=Quotes= by Ronald de Man in a reply to Guy Haworth, April 06, 2013 : ||

=Endgame News= In his 2014 //Chess Endgame News// in ICGA Journal, Vol. 37, No. 2, Guy Haworth classified Syzygy Bases as **new** data in **three** ways: > +2 ≡ unconditional win for the side to move > +1 ≡ ‘win’ which can be frustrated by best play and a 50mr draw-claim > _ 0 ≡ unconditional draw > -1 ≡ ‘loss’ saved by a 50mr draw-claim > -2 ≡ unconditional loss
 * 1) 5-valued scale for evaluating positions in the context of the FIDE 50-move rule (50mr) which constrains the length of phases of play
 * 1) depths for ‘50mr draw’ positions with value ±1
 * 2) depths in symmetric, information-preserving ply ‘p’

and further gives some news about early software bugs and glitches concerning ChessBase products, and the importance of [|MD5] to check the EGT integrity.  =Fathom=
 * Fathom** is a stand-alone Syzygy based probing tool and [|API] by Basil Falcinelli, introduced in November 2015 along with his Gull 3 release . Unlike the original tbprobe code, Fathom does not necessarily require the callee to provide move generation functionality. The new modifications and extensions to Ronald de Man's original code which can be "redistributed and/or modified without restrictions", are released under the permissive MIT License. The API consists of three functions :
 * initializes the tablebase
 * probes the Win-Draw-Loss (WDL) table for a given position
 * probes the Distance-To-Zero (DTZ) table for the given position.

Jon Dart has a fork of Fathom with some bug fixes and enhancements. .
 * See also**
 * Bitbases
 * Edwards' Tablebases
 * Gaviota Tablebases
 * Lomonosov Tablebases
 * Nalimov Tablebases
 * python-chess
 * Scorpio Bitbases
 * Thompson's Databases

=Publications=
 * Guy Haworth (**2014**). //Chess Endgame News//. ICGA Journal, Vol. 37, No. 1
 * Guy Haworth (**2014**). //Chess Endgame News//. ICGA Journal, Vol. 37, No. 2
 * Guy Haworth (**2014**). //Chess Endgame News//. ICGA Journal, Vol. 37, No. 3 » Fritz 14

=Forum Posts=

2013 ...

 * [|New 6-piece tablebases] by Ronald de Man, CCC, April 01, 2013
 * [|New 6-piece tablebase generator] by syzygy, CCRL Discussion Board, April 01, 2013
 * [|Re: PEXT Bitboards] by Ronald de Man, CCC, June 07, 2013 » BMI2 - PDEP, BMI2 - PEXT
 * [|Syzygy EGTB's via Torrent Thread] by Joshua Shriver, CCC, September 11, 2013
 * [|Syzygy tablebases, work in Stockfish?] by Jose Mº Velasco, CCC, September 23, 2013 » Stockfish
 * [|Building Syzygy bases] by higgs, Rybka Forum, October 12, 2013
 * [|tablebase caching / mmap / page cache] by Ronald de Man, CCC, October 13, 2013 » Memory
 * [|Syzygy endgame tables: Generation and first impressions] by Mike Scheidl, CCC, October 15, 2013
 * [|deMan TB Path and Cache] by Matthias Gemuh, CCC, October 19, 2013
 * [|syzygy TB (3-4-5 men only) download link ?] by MarshallArts, Rybka Forum, October 21, 2013
 * [|rkiss and other dependencies in syzygy] by Don Dailey, CCC, October 23, 2013
 * [|Syzygy / egbb discussion] by Daniel Shawul, CCC, October 23, 2013 » Scorpio Bitbases
 * [|Manual: How to use Syzygy (or any other) 6-men without SSD] by Milos Stanisavljevic, CCC, November 16, 2013
 * [|potential deadlock in syzygy reference implementation] by Richard Vida, CCC, November 23, 2013
 * [|Re: A note for C programmers] by Marcel van Kervinck, CCC, November 27, 2013
 * [|Stockfish Syzygy: how to interpret mates?] by Jouni Uski, CCC, December 01, 2013 » Stockfish, Mate Scores
 * [|Problem with 6-piece syzygy-bases using wine] by Bernhard Bauer, CCC, December 05, 2013
 * [|ChessGUI 0.245f is available] by Matthias Gemuh, CCC, December 14, 2013 » ChessGUI
 * [|Syzygybases suitable for win32-systems?] by Norbert Raimund Leisner, CCC, December 17, 2013
 * [|Syzygy Tablebases list of importance] by chri$, OpenChess Forum, December 21, 2013
 * [|Syzygy options] by Harm Geert Muller, CCC, December 27, 2013
 * 2014**
 * [|Ideal Syzygy Probe Depth ? (using SSD)] by Anil V Dharan, CCC, January 14, 2014
 * [|SYZYGY Base question] by Ingo Bauer, CCC, January 19, 2014
 * [|problem with syzygy tablebases] by Youri Matiounine, CCC, February 01, 2014
 * [|Performance of Syzygy and Scorpio] by Kai Laskos, CCC, February 04, 2014 » Scorpio Bitbases
 * [|A question about syzygy] by Enrico Tognoni, CCC, February 26, 2014
 * [|A question about syzygy 6 men and partial use] by Enrico Tognoni, CCC, February 26, 2014
 * [|Syzygy on RAM Drive] by Kai Laskos, CCC, May 23, 2014 » Stockfish, Komodo 7, Houdini 4
 * [|Re: Syzygy tb generator for windows] by syzygy, CCRL Discussion Board, June 01, 2014
 * [|Question about syzygy bases] by Gabor Szots, CCC, June 02, 2014
 * [|Re: 7-piece syzygy] by syzygy, CCRL Discussion Board, July 03, 2014
 * [|Question on Stockfish and SyzygyCache UCI option] by Erfuk Neuni, CCC, December 07, 2014
 * [|USB 3 Storage for Syzygy WDL files] by Louis Zulli, CCC, December 13, 2014 » USB 3.0

2015 ...
> [|Re: Stockfish 7 and partial 6 piece syzygy problem?] by Marco Costalba, CCC, September 01, 2016
 * [|Komodo 8 - 5-men Syzygy tablebases] by Andreas Strangmüller, CCC, January 10, 2015 » Komodo 8
 * [| Problem with SF6 and Syzygy TB] by Forrest Hoch, CCC, April 01, 2015 » Stockfish
 * [|SD Syzygy] by [|Ted Summers], CCC, April 26, 2015
 * [|5 men Syzygy on USB 3.0 Flash Drive] by Kai Laskos, CCC, May 09, 2015
 * [|Re: how to probe egtb from console?] by Ronald de Man, CCC, May 15, 2015 » python-chess
 * [|Gull 3 Linux+Syzygy and Fathom released] by Basil Falcinelli, CCC, November 20, 2015 » GullChess, Fathom
 * [|Syzygy probing code: DTZ in some cursed endgames off by one?] by Niklas Fiekas, CCC, December 06, 2015
 * 2016**
 * [|Re: Squash anyone?] by Ronald de Man, CCC, February 07, 2016
 * [|My troubles with MultiPV and Syzygy in Stockfish 7] by Árpád Rusz, CCC, February 16, 2016
 * [|Stockfish 7 and partial 6 piece syzygy problem?] by Jouni Uski, CCC, March 01, 2016 » Stockfish
 * [|Arasan Syzygy support (working with Windows, too)] by Jon Dart, CCC, March 10, 2016 » Arasan
 * [|Question to syzygy author] by Marco Costalba, CCC, April 24, 2016
 * [|syzygy question] by Robert Hyatt, CCC, May 04, 2016
 * [|question about syzygy probing] by Marco Belli, CCC, May 21, 2016
 * [|Natural TB] by Marco Costalba, CCC, May 29, 2016 » Stockfish
 * [|syzygy questions] by Robert Hyatt, CCC, July 06, 2016
 * [|How texel probes endgame tablebases] by Peter Österlund, CCC, July 16, 2016 » Gaviota Tablebases, Texel
 * [|Syzygy and draw by repetition] by Jon Dart, CCC, July 22, 2016 » Draw, Repetitions
 * [|Syzygy question] by J. Wesley Cleveland, CCC, September 03, 2016
 * [|Suicide chess tablebases (stalemated player wins)] by Niklas Fiekas, CCC, October 25, 2016 » Losing Chess
 * [|Syzygy tablebases] by Andy Leese, CCC, December 01, 2016
 * [|Help for Syzygy probe?] by Ted Wong, CCC, December 04, 2016 » Fathom
 * 2017**
 * [|6-men Syzygy from HDD and USB 3.0] by Kai Laskos, CCC, April 04, 2017 » Komodo, Playing Strength, USB 3.0
 * [|Fathom memory usage] by Álvaro Begué, CCC, June 22, 2017» Fathom
 * [|RuyDos with support for syzygy tablebases] by Álvaro Begué, CCC, June 23, 2017 » RuyDos
 * [|Natural TB (take 2)] by Marco Costalba, CCC, August 22, 2017 » Stockfish
 * [|Probing tablebases through USB 3.0] by Jon Fredrik Åsvang, CCC, September 25, 2017 » USB 3.0
 * [|understanding DTZ] by Alexandru Mosoi, CCC, October 06, 2017 » DTZ, Fathom
 * [|Is there now coming changes to syzygy databases?] by Jouni Uski, CCC, November 13, 2017 » DTM, CFish
 * [|How to Download Syzygy Endgame Tablebase Files] by Daniel Johnson, CCC, December 23, 2017
 * 2018**
 * [|The history of Syzygy tablebases] by Isaac Haïk Dunn, CCC, March 06, 2018
 * [|7-men Syzygy attempt] by Bojun Guo, CCC, March 10, 2018
 * [|Syzygy implementations of top engines] by Kai Laskos, CCC, March 14, 2018
 * [|Probing the Syzygy tablebase - beginners question] by Andreas Matthies, CCC, April 16, 2018

=External Links=

Tablebase

 * [|syzygy1/tb · GitHub] by Ronald de Man
 * [|jromang · GitHub] by Jean-Francois Romang has a fork from syzygy1/tb
 * [|python-chess/syzygy.py at master · niklasf/python-chess · GitHub] by Niklas Fiekas, Python implementation of probing code » python-chess
 * [|niklasf/syzygy-tables.info · GitHub] by Niklas Fiekas, GUI and public API for Syzygy probing
 * [|Syzygy endgame tablebases Web Interface] - Syzygy online lookup
 * [|OICS Chess and EGTB Tracker Statistics] by Joshua Shriver
 * [|Endgame Tablebases Online] by Kirill Kryukov
 * [|Index of /tablebases/syzygy (3,4,5)] by kingliveson
 * [|tablebase.sesse.net] by Sesse

Fathom

 * [|GitHub - basil00/Fathom: Syzygy TB probe tool] by Basil Falcinelli
 * [|jdart1/Fathom · GitHub] by Jon Dart (with some bug fixes and enhancements)

ChessBase

 * [|Syzygy Tablebases: newest, fastest, smallest] by Albert Silver, ChessBase News, February 08, 2015
 * [|Syzygy tablebases: maximizing performance] by Albert Silver, ChessBase News, February 10, 2015
 * [|Endgame Turbo 4] by ChessBase

Misc
> Michael Brecker, Mike Stern, [|Jeff Andrews], [|Adam Nussbaum], [|Joey Calderazzo] > media type="youtube" key="lgVxFM7cONQ"
 * [|syzygy - Wiktionary]
 * [|Syzygy (disambiguation) from Wikipedia]
 * [|Syzygy (astronomy) from Wikipedia]
 * [|Syzygy (mathematics) from Wikipedia]
 * [|Caledonian Antisyzygy from Wikipedia]
 * Michael Brecker Band - [|Syzygy], August 16, 1987 at [|Newport Jazz Festival], [|YouTube] Video

=References= =What links here?= include page="Syzygy Bases" component="backlinks" limit="120"
 * Up one level**