Chiron in the IGT 2018

During the weekend of October 27-28, Chiron played in the 2018 International GSEI Tournament organized this year by Stefano Gemma. The playing venue was the GAP in Borgo Virgilio, Mantova. Nine progams played a single round-robin. The time control was 25’+10″. Jonny by Johannes Zwanzger won the tournament. Chiron finished second while Pedone by Fabio Gobbato was third after winning the tie-break against The Baron by Richard Pjil. Congratulations to Johannes for a well deserved win. As first of the italians, Chiron is the 2018 Italian Champion. For the first part of tournament, Chiron ran on the same 60 cores Xeon v2 used last year (thanks Wolfgang), and for the remaining games on my 32 cores server with two Opteron 6274, except for the game against The Baron for which an Amazon EC2 instance was used. Jonny ran on a cluster with 384 cores while all the others used local hardware. PICcolino by Luca Naddei runs on a 70 MHz PIC inside a chess board made by Luca himself. Near the end of the tournament a man vs machine match was played: the FIDE Master Valerio Luciani (~2200) played two games against Adachess by Alessandro Iavicoli that won the match. You can find the standings and all the games on GSEI website.

Chiron in the WCCC 2018

From July 13 to 19, Chiron played in the World Computer Chess Championships organized by the ICGA, at the Stockholmsmässan in Stockholm. The hardware for Chiron was provided by the E4 Computer Engineering: a server configured with 2 x AMD Epyc 7551 (64 cores), 256GB of RAM and a very fast Intel Optane P4800X for the Syzygy bases. The average speed was 50/60 MNPS in the middlegame. Chiron placed shared second in the World Computer Speed Chess Championship (12 games, tc 5’+5″). If I had not made it lose a game against Ginkgo by playing a wrong move on the board, it could have been clear second but these things can happen during the blitz tournament. In the World Chess Software Championship all the participants had to use the same hardware: a notebook with an i7-8550U 1.8GHz quad core CPU and 16GB of RAM. The time control was 45’+15″. Chiron scored 4/8 and its only loss was against Jonny after playing the very dubious 16.h3. On Monday 16, the World Computer Chess Championship started. The tc was 1h45’+15″ for 7 games. There was much interest on the WCCC because Leela Chess Zero would have played. Chiron has not a lost a single game but unfortunately has not won one either, thus placed fourth in the WCCC, half a point behind the third. Komodo won all the three championships. Congratulations to its team. The ICML and the IJCAI-ECAI took place in the same days and many partcipants showed interest in our tournaments, following the games, the commentary by GM Harry Schüssler and making questions. This was probably the best computer chess tournament I played in. You could talk with many interesting people from the AI field and some of them also played against our engines, like Prof. Tuomas Sandholm, cocreator of Libratus, who played 4 games against Chiron, almost drawing the last one and thus showing once again I have to work on Chiron’s tendency to trade off all its pieces. Finally, many thanks to the E4 Computer Engineering, in particular to Agnese Reina and Marco Cicala, that let Chiron run on one of their fast servers and prompty solved any technical problem I had.
You can find more info about the WCCCs on the ICGA site and on their Facebook page.

Here are some photos and the games played by Chiron:

Chiron wins IGT 2017

Chiron has won the International GSEI Tournament 2017. The tournament was played on September 23-24 in Rome. Once again, the playing venue was the Accademia Scacchistica Romana. Fourteen programs played 7 rounds. The time control was 30’+10″. Chiron shared the first place with Jonny and then won the tie-break at 5’+5″ by 1.5-0.5. You can find all the results and the games on GSEI’s website. Many thanks to Erdogan Gunes and Wolfgang Zugrav, from Komodo’s Team, for providing the opening book and the very fast hardware Chiron ran on (60 core Xeon v2 @ 2.5GHz). Chiron searched about 60 Mnps in the middlegame and 80 Mnps in the endgame, reaching 100+ a couple of times.

Chiron 4 released

Chiron 4 is about 70 points stronger than Chiron 3.

Here’s a list of the main changes:
– improved automatic tuning of the evaluation
– improved evaluation of passed pawns, mobility, opposite bishops endings
– improved forward pruning in the search
– improved LazySMP for parallel search
– support for Windows Processor Groups (more than 64 threads can now be used)
– NUMA optimization (new UCI and Winboard options “NUMA”)
– minor speed optimizations
– fixed a pondering bug
– fixed two time management bugs under the Winboard protocol

Chiron 4 is available for Windows and Android.
Buyers of the Windows version will also receive a code to get the Android one for free.

Chiron 2/3 Customers can buy Chiron 4 with a discount through the link they have reiceved. Whoever has bought Chiron 3 in the last month will receive Chiron 4 for free.

Chiron wins IGT 2016

Chiron has won the 2016 edition of the International GSEI Tournament. The playing venue should have been at Il Capisterium in Norcia but, because of the earthquake that struck the area, the tournament was held at Accademia Scacchistica Romana in Rome, on September 10-11. There were ten participants, the time control was 30′ + 10″ for 7 rounds. Chiron finished ahead of Booot by half a point. You can read more on GSEI’s website. Thanks to Jeroen Noomen who provided the opening book for Chiron.

Chiron 3.01 released

Chiron 3.01 is a bugfix version.
There was a bug that would often make Chiron crash when Syzygy bases were used.

Thanks to Antonello R. and Christian G. for reporting and helping with testing.

Chiron 3 released

Chiron 3 is about 60 points stronger than Chiron 2.

Now also available on Android:

Here’s a short list of changes:
– improved search (better parameters for pruning and move ordering)
– improved evaluation (in particular mobility and king safety)
– tuning of the evaluation
– new parallel search
– added support for Syzygybases
– added option “Tablebases Probe Depth” (default=6, lower it if you have a SSD)
– 6 pieces Scorpio bitbases can now be probed
– improved time management
– fixed a time management bug for X moves in Y minutes time controls (thanks to Gabor Szots)
– added option “Blockage Detection” to enable/disable pawn blockage detection
– added again support for CTG books

It comes with an improved Polyglot opening book developed by Arturo Ochoa.

Who has bought Chiron 2 in the last month will receive Chiron 3 for free.
Past Customers can buy it with a discount through the link received in an email.

Chiron in Ubisoft’s Watch Dogs

Chiron has been chosen by Ubisoft for the chess mini game in its highly anticipated open world action game Watch Dogs. The player controls Aiden Pearce, a grey hat hacker obsessed with security and surveillance, and can play throughout the Chicago area normal chess games or try to solve puzzles to increase Aiden’s focus skill.
Of course, given the wide audience, a highly modified reduced strength version of Chiron was used.



Here are a couple of chess related screenshots from the game.

New Book for Chiron 2

Arturo Ochoa has made and kindly offered an opening book for Chiron 2 customers.
It is a wide balanced Polyglot book (~76MB) made from a selection of human and computer games from 2013. You should have received an email with a link to download it.

My thanks to Arturo and my best wishes for Christmas!

Chiron 2 released

Chiron 2 is about 40 Elo points stronger than Chiron 1.5 thanks to improvements in both search and evaluation functions.
Parallel search and time management have been improved too.
Several ChironBitbases have been integrated in the executable:
as well as 4 tablebases: KPK, KRK, KQK and KPKP with rammed pawns.
Besides that, some bugs have been fixed:
– Chiron would often crash with multi-socket systems
– Gaviota tablebases were rarely probed

I would like to thank Martin Thoresen and Ingo Bauer that have helped with testing.