What happened for Stockfish at Move 47...?

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thomasahle
Posts: 94
Joined: Thu Feb 27, 2014 8:19 pm

What happened for Stockfish at Move 47...?

Post by thomasahle »

In the latest TCEC game that Lc0 won, near the end, Stockfish showed a 2600cp advantage for white, but then for one move it dropped down to 176cp before going back up to an impressive 7913.

Game here: http://legacy-tcec.chessdom.com/archive ... 4&sf&ga=29

Presumably this was a bug that got revealed.
But it could also have been an expected search discontinuity or transposition table clash.
Any clues to what might have caused it?
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silentshark
Posts: 327
Joined: Sat Mar 27, 2010 7:15 pm

Re: What happened for Stockfish at Move 47...?

Post by silentshark »

Isn't it just a case that that was a forced move, i.e. the king move was the only legal move so SF played instantly w/out searching?
RubiChess
Posts: 584
Joined: Fri Mar 30, 2018 7:20 am
Full name: Andreas Matthies

Re: What happened for Stockfish at Move 47...?

Post by RubiChess »

silentshark wrote: Sun Feb 10, 2019 11:08 am Isn't it just a case that that was a forced move, i.e. the king move was the only legal move so SF played instantly w/out searching?
Yes. So called "instamove". Maybe it would be a good idea to output the score of the evaluation of the previous position again instead of the useless eval at depth 1.

./Andreas
thomasahle
Posts: 94
Joined: Thu Feb 27, 2014 8:19 pm

Re: What happened for Stockfish at Move 47...?

Post by thomasahle »

Ah, that's interesting. In that case I would have thought it returned whatever was in the transposition table.
But maybe it doesn't even use the table in this case.