Google's AlphaGo team has been working on chess

Discussion of chess software programming and technical issues.

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Joerg Oster
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Re: Google's AlphaGo team has been working on chess

Post by Joerg Oster »

jdart wrote:Stockfish does such heavy pruning that it is throwing away most of the nodes in its search trees. But the ones it does search, it searches very deeply. I see a lot of high-level computer games won by tactics or by endgame play that requires deep search. Shannon Type II (selective search) has never worked well in any of the past 5-6 decades. But maybe this effort is showing that eval is more important than has been thought, and search less important.

--Jon
And quite remarkably it is both, one of its biggest strength but also one of its biggest weakness. :lol:
Jörg Oster
Rein Halbersma
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Re: Google's AlphaGo team has been working on chess

Post by Rein Halbersma »

mar wrote:While this is indeed incredible, show me how it beats SF dev with good book and syzygy on equal hardware in a 1000 game match.

Alternatively winning next TCEC should do :wink:
Equal budget would be a fairer comparison since AlphaZero and Stockfish take advantage of different types of hardware (GPU vs CPU).

If you look at the scaling graph of thinking time vs performance, it suggests that Stockfish is still ahead at fast time controls but that at longer time controls AlphaZero dominates. It would be interesting to see this graph as a function of money resources.
CheckersGuy
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Re: Google's AlphaGo team has been working on chess

Post by CheckersGuy »

Rein Halbersma wrote:
mar wrote:While this is indeed incredible, show me how it beats SF dev with good book and syzygy on equal hardware in a 1000 game match.

Alternatively winning next TCEC should do :wink:
Equal budget would be a fairer comparison since AlphaZero and Stockfish take advantage of different types of hardware (GPU vs CPU).

If you look at the scaling graph of thinking time vs performance, it suggests that Stockfish is still ahead at fast time controls but that at longer time controls AlphaZero dominates. It would be interesting to see this graph as a function of money resources.
That's the difficult thing with AlphaZero. Comparing two different types of hardware is not that easy. One could use a performance/dollar metric or performance/power-usage.

I personally prefer performance/dollar +performance/power-usage
jdart
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Re: Google's AlphaGo team has been working on chess

Post by jdart »

Well, probably they should have give same FLOPS budget to both, that seems like the most fair you can get, given the inefficiency of switching hardware for either side.
Here is a scary thought, though: what would be the performance of AlphaZero if they used more of its training cluster for execution?

I don't know how well it scales on more TPUs and it might need tuning for that but throwing even more processors on it could put it even more even with Stockfish, if not above it.

They could possibly enter the WCCC with that.

--Jon
CheckersGuy
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Re: Google's AlphaGo team has been working on chess

Post by CheckersGuy »

jdart wrote:
Well, probably they should have give same FLOPS budget to both, that seems like the most fair you can get, given the inefficiency of switching hardware for either side.
Here is a scary thought, though: what would be the performance of AlphaZero if they used more of its training cluster for execution?

I don't know how well it scales on more TPUs and it might need tuning for that but throwing even more processors on it could put it even more even with Stockfish, if not above it.

They could possibly enter the WCCC with that.

--Jon
As far as I know the first generation TPU's, which were used for training, are for training only. The second generation TPU'S can do both training and inference.
However, google/deepMind probably has enough hardware to use many many more second generation TPU's. What I am intrested in is, when the AI stop's improving in the training process since they only trained for 4 hours.
Henk
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Re: Google's AlphaGo team has been working on chess

Post by Henk »

Building neural network software from scratch is much work.
corres
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Re: Google's AlphaGo team has been working on chess

Post by corres »

[quote="Rein Halbersma"]

[b]Equal budget[/b] would be a fairer comparison since AlphaZero and Stockfish take advantage of different types of hardware (GPU vs CPU).
If you look at the scaling graph of thinking time vs performance, it suggests that Stockfish is still ahead at fast time controls but that at longer time controls AlphaZero dominates. It would be interesting to see this graph as a function of money resources.

[/quote]

I am afraid that Stockfish does not get significant help from a much more expensive hardware than it was used for demonstration of AlphaZero.
Supposing the 64 cores used by them are physical cores and not logical cores the increase of cores number to 128, 256,.. give some ten Elo only.
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stegemma
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Re: Google's AlphaGo team has been working on chess

Post by stegemma »

corres wrote:
Rein Halbersma wrote:
Equal budget would be a fairer comparison since AlphaZero and Stockfish take advantage of different types of hardware (GPU vs CPU).
If you look at the scaling graph of thinking time vs performance, it suggests that Stockfish is still ahead at fast time controls but that at longer time controls AlphaZero dominates. It would be interesting to see this graph as a function of money resources.
I am afraid that Stockfish does not get significant help from a much more expensive hardware than it was used for demonstration of AlphaZero.
Supposing the 64 cores used by them are physical cores and not logical cores the increase of cores number to 128, 256,.. give some ten Elo only.
I think that this a limit of alphabeta algorithm, not a limit of Stockfish itself. The limit of alphabeta is derived by the nature of the game, of course, that grows exponentially at any ply. A smarter approach that uses neural networks and/or other AI algorithms could potentially gives better performance than alphabeta (as AphaZero seems to "demonstrate"). of course AI requires more computational power than alphabeta based algorithms but could eventually scale better at time/power increasing.
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CheckersGuy
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Re: Google's AlphaGo team has been working on chess

Post by CheckersGuy »

I think working on a similar engine to AlphaZero would be really intresting. One will obviously not get the same performance as AlphaZero but it would still be intresting to see, how well the algorithm scales (with additional hardware and time) compared to current state of the art engines.
brianr
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Re: Google's AlphaGo team has been working on chess

Post by brianr »

See here:

https://github.com/Zeta36/chess-alpha-zero

I have gotten it to work, but it is painfully slow with just one gpu.

LeelaZero is trying a more distributed approach like Fishtest, albeit for Go.

https://github.com/gcp/leela-zero