Second 2011 Slow KGS Computer Go Tournament

May 22nd-27th 2011

These results also appear on an official KGS page which also links to the records of all the games.


format20-round Swiss
board size19×19
timeThree hours each, sudden death


The first round started at 22:00 UTC on the evening of Sunday 22nd.

Result table

Zen19 pachi ManyF AyaMC Stone Czech PNUGo dbot
B13R W09R B113R W117R B14R W18R B114R W116R B16R W110R B115R W120R W12R B112R W119R B07R W111R W11R B118R B15R 18210187Winner
2pachi2 W03R B19R W013R B017R
W05R B010R W118R B019R W120R B12R W112R B116R W17R B111R B16R W18R W140.5 B115R B11R W114R 14218125
3ManyFaces1 W04R B08R W014R B016R B15R W110R B018R W119R B020R
B01R W19R B13R W115R B12R W112R B113R W17R B11125.5 B16R W117R 13221110
4AyaMC W06R B010R W015R B020R W02R B012R W016R W11R B09R
B15R W18R B117R B04R W114R B119R W1312.5 B11319.5 W17R B111R W118R 1120771
5StoneGrid B02R W012R B019R B07R W011R W03R B015R W05R B08R W017R
W11R B116R W118R W161.5 B1101.5 W11418.5 B120R B14R W19R B113R 1018847
6CzechBot W17R B011R W06R B08R W02R B012R W013R W14R B014R W019R B01R W016R B018R
B151.5 W190.5 B1175.5 B13R W110R B115R W120R 918144
7PNUGo B01R W018R B040.5 W015R B07R W01125.5 B0312.5 W01319.5 B061.5 W0101.5 B01418.5 W020R W051.5 B090.5 W0175.5
W12R B18R W112R B116R W119R 51790
8dbot W05R W01R B014R W06R B017R B07R W011R B018R W04R B09R W013R W03R B010R W015R B020R B02R W08R B012R W016R B019R

In the table above,
   0 indicates a loss
   1 indicates a win
   a superscript indicates the round in which a game was played
   a subscript shows how the result was determined:
      R for resignation
      T for time
      F for forfeit
      a number for the points difference after counting.
All the 0s, 1s and Js are links to the game record.

Shortly before the start of play, there were seven players registered. I then received an email from Detlef Schmicker, asking to register his program 'dbot'. He did not persuade me that it was strong enough to enter (the criterion is "have beaten SimpleBot"). However I considered it better to have dbot playing than to have byes, and allowed it to enter.

Thus eight players registered. All played all their games.


ManyFaces1 vs AyaMC
Moves 213-218.

In round 7, CzechBot beat Zen19S. This was Zen19S's first loss.

In round 9, pachi2 beat Zen19S. This was Zen19S's only other loss.

Also in round 9, there was an interesting game between AyaMC and ManyFaces1, involving a semeai at the lower left side of the board, as shown to the right. This is a semeai in which White has a big eye and Black a small eye, so Black should win.

However, after move 270, with the position in the lower left unchanged, AyaMC resigned as Black. It had failed to realise that it can capture the 23-stone white group. If it had captured it, it would have won the game.

pachi2 vs AyaMC
Moves 109-111.

In round 12, pachi2 appeared to misread a snapback against AyaMC, as shown to the left. Its move 10 captures three stones, but fails to prevent Black's D7 and D8 stones from connecting to its right-side group.

The players receive points for the 2011 Annual KGS Bot Championship as follows:

Many Faces of Go3

Details of processor numbers, power, etc.

Aya, running on a 980X 3.3GHz 6 cores
a development version of MoGo current as of 2010-10-06, running on an 8-thread i7 920, 6GiB RAM
dbot, running on a single-thread Mac mini
Many Faces of Go, running on 8 cores.
GNU Go, running on a 2-core system, probably a Core2 Duo E7200 2.53GHz
pachi, running on 32 unspecified 22-core platforms.
StoneGrid, running on an Intel Core2 Quad Q9400 (2.66GHz, 6MB L2, 1333Mhz FSB)
Zen, running on a 6-core Xeon for rounds 1 to 9 and a 6-pc personal cluster for rounds 10 to 20. The cluster consisted of a 6x3.3 GHz Xeon W3680, two 4x3.2 GHz i7 920 and three 4x3 GHz Core2Quad.