Changes

Syzygy EGTB is significantly smaller than all any [[Endgame Tablebases#DTM|DTM]] EGTBsEGTB. It is 7 times as small as Gaviota for 5 men, 8 times as small as Nalimov for 7 6 men, 8 times as small as Lomonosov for 7 men. However, when all DTM EGTBs have full data of two sides, Syzygy EGTB omits data of one side for DTZ data to save space. [[Ronald de Man]] estimated if keep them all, the Syzygy's 6 men size may increase 158 GB, become 307 GB in total, double on size, 4 times as small as Nalimov 5 6 men.

On the first release (Apr 0201, 2013) the generator was ready to generate all endgames up to 6 men. The generation is multithreaded and processed processes completely in RAM. To generate all 6 men, it requires a system with at least 32 GB of RAM and working may run in 5 days (the period was measured with a computer 6-core i3930K @ 4.2Ghz, 64 GB).

Ronald de Man wasn't initially interested in the creation of 7-men Syzygy Based <ref>[http://kirill-kryukov.com/chess/discussion-board/viewtopic.php?f=6&t=7618#p83771 Re: 7-piece syzygy] by [[Ronald de Man|syzygy]], [[Computer Chess Forums|CCRL Discussion Board]], July 03, 2014</ref>. His original generator could not create them. But in 2018, he supported [[Bojun Guo]] in his 5 month attempt to generated them <ref>[http://www.talkchess.com/forum/viewtopic.php?t=66797 7-men Syzygy attempt] by [[Bojun Guo]], [[CCC]], March 10, 2018</ref>. The since the generation of 7-man tablebases would require about 1 TB of RAM, estimated cost over US$ 90Ktoo expensive at that time. Generation time will would be about 64 x per table, which means around 175 x time total <ref>[http://kirill-kryukov.com/chess/discussion-board/viewtopic.php?f=6&t=7396#p83338 Re: Syzygy tb generator for windows] by [[Ronald de Man|syzygy]], [[Computer Chess Forums|CCRL Discussion Board]], June 01, 2014</ref>.His original generator could not create them. But in 2018, he supported [[Bojun Guo]] in his 5-month attempt to generated them <ref>[http://www.talkchess.com/forum/viewtopic.php?t=66797 7-men Syzygy attempt] by [[Bojun Guo]], [[CCC]], March 10, 2018</ref>. His hardware was estimated at over US$ 90K. In August of 2018 their creation was completed<ref>[https://syzygy-tables.info/ Powered by Ronald de Man's Syzygy endgame tablebases, 7-piece tables generated by Bojun Guo and a public API hosted by lichess.org], August 19, 2018</ref><ref>[http://tablebase.lichess.ovh/tables/standard/7/ Index of /tables/standard/7/ on lichess], August 19, 2018</ref>.

[[Ronald de Man]] has provided only open source code for generators/probers but not endgame files themselves. Using his tools some people have generated endgames and published them via DVD or online such as FTP servers of [[Bojun Guo]] and [[Lichess]].