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Number of Legal 18x18 Go Positions Computed; 19x19 On the Horizon

Posted by timothy on from the now-we'll-call-it-gone dept.

johntromp writes It took about 50,000 CPU hours and 4PB of disk IO, but now we know the exact number of legal 18x18 Go positions. Seeking computing power for the ultimate 19x19 count. And it's not a heat-death-of-the-universe kind of question, either, they say: "Thanks to the Chinese Remainder Theorem, the work of computing L(19,19) can be split up into 9 jobs that each compute 64 bits of the 566-bit result. Allowing for some redundancy, we need from 10 to 13 servers, each with at least 8 cores, 512GB RAM, and ample disk space (10-15TB), running for about 5-9 months."

7 of 186 comments (clear)

  1. I know it is a bit late in life... by KGIII · · Score: 3, Interesting

    However, I think I'd like to learn to play this game. I played chess at an amateur level and did rather well at it during and even after college. I don't know if any of the skills transfer but I've been told that the mentality transfers. Being able to look a half dozen or more moves ahead and being able to picture all the moves my opponent can make are, as I have been told, something that does transfer.

    --
    "So long and thanks for all the fish."
    1. Re:I know it is a bit late in life... by shadowofwind · · Score: 4, Interesting

      Chess mentality doesn't transfer very well to go in my observation. Since go has vastly more plausibly good moves, chess players often find themselves not understanding how to choose where to go next. Most people I've known who like go a lot hate chess. I've known one person who likes both, and he was never able to get very good at go. Generally speaking, chess can be learned by someone who can think logically and learn the standard opening sequences. Go is more like painting. Its not necessarily a superior skill, but not all intellectually-smart people are smart in the right way.

      But by all means learn, its easy to get a game on the internet. If you like it its worth it. And if you do it for ego and discover you suck, sometimes that's worth something too.

    2. Re:I know it is a bit late in life... by JanneM · · Score: 4, Interesting

      To be honest, as a kid I enjoyed chess and played with my friends right up to the point where you suddenly had to start memorizing openings and other canned sequences. At which point it felt more like a school subject than an escape from it.

      --
      Trust the Computer. The Computer is your friend.
    3. Re:I know it is a bit late in life... by AthanasiusKircher · · Score: 4, Interesting

      I have to agree with this. I loved chess as a little kid -- probably started playing when I was 4 or so. Always just played for fun and liked the way it was more complex than something like checkers. I also occasionally enjoyed puzzling out some of those chess puzzles in the newspaper, which usually involved endgame scenarios. But then, early in middle school, I played against someone who actually "knew what he was doing," which included things like memorized openings, basic tactics, and canned strategies. He was kinda dumb but nonetheless beat me handily. I spent a month or two learning openings and such, and suddenly I could beat most of my friends (including those quite a bit older) pretty consistently too, just from the improved board positions.

      At that point I realized that becoming a "real chess player" was very different from the fun I'd been having, and I completely lost interest. I've only played a handful of times since, mostly because it's really hard to have any fun playing with my knowledge -- not enough to play "real chess" against anyone who studied strategy, but too much to play against the people who know the basic rules but never learned that stuff.

      I admire the grandmasters, because they have both that amazing set of memorized knowledge AND the incredible logic/intuition. But I have absolutely no desire to play the game anymore because while I'm somewhat interested in the latter, I can't be bothered with the former. It's permanently ruined for me.

  2. My two by Anonymous Coward · · Score: 3, Interesting

    I also took chess quite seriously for a few years, reaching approximately 1800. The pervasiveness of rote openings discouraged me a bit, but I always loved the game and still do. However, I abandoned it for Go, where I hold a shameful but enjoyable rating of 6-7kyu. I have never found any aspect of Go, other than scarcity of oponents , worth complaining about. It is, perhaps, the world's only perfect game. Just remember to lose your first 50 games as quickly as possible. Afterwards, expect a lifelong companion.

  3. Re:So what's the end goal of this? by Anonymous Coward · · Score: 3, Interesting

    hey man, don't be a prick

    go is super interesting from a formalistic perspective given that it has an extremely large amount of emergent behavior.

    that is, the rules are so simple, that it should really be as easy to analyze as connect 4

    but its likely the most complicated full-information game created by man

    so, no, the exactly number isn't particularly interestingbut give the guy a break. 'mathematical go' by berlekamp is pretty
    boring and trite and focusses on some really uninteresting endgame positions. but he tried to get a handle on things.

    john tromp, one of the contributing authors, has made some very cool contributions on the solvability of go, the exact nature
    of the rulesets, various automated processes for studying go positions, library software for keep track of the best human move
    in a given position, etc etc.

    so stfu

  4. Re: How Much Does it Cost? by garyisabusyguy · · Score: 3, Interesting

    Yeah, $200k seems a bit steep. I mean, if it was for national defense, pushing data against the stock market, or even running a moderately sized corporation's ERP stack it would be a totally acceptable expenditure

    It is an interesting problem to posit how it would be possible to get the same gear for a fraction of the cost, say 10%, or $20k

    This may seem wildly optimistic, but in the dot-com meltdown I remember seeing gear with million dollar price tags going for $10k on ebay

    The chassis, processors, and potentially even disk arrays may be easily obtained. I have worked at companies where they were shoved out the loading dock door on a monthly basis, because newer gear had smaller footprints and we could stuff ten times as many processors or terabytes into the same constrained space that we were stuck with

    RAM may be a problem since they are asking for 512GB per machine. This would probably be in 32GB sticks, which are as easily traded as gold, and even if a company was shit-canning them, the more enterprising techs should be expected to be grabbing them at every opportunity

    The common nexus for this gear would be the computer salvage companies that get paid to haul it away and make a secondary profit off of reselling what they can. How would these go-crackers find a salvage company with similar leanings? If that connection could be made, they may get away with it for the discounted cost of re-sold RAM

    Which leads us to the next issue, supplying 15KW of juice to run these on, the additional power to pull that heat out of the space and enough battery supply to handle a power outage without losing your entire data set. In the corporate world, this is another $50k of Liebert gear and a diesel generator. And your gonna have somebody on-call to monitor, tune and otherwise tend to their wants and needs...

      in cheapo-town... this could be a garage and a stack of deep-cell batteries with the over-worked go-crackers reheating pizza on the top of a server

    I think that it is an interesting exercise to figure out how to deliver a half-million dollar hardware solution for next to nothing, anybody else have their 2-bits to throw at it?

    --
    Wherever You Go, There You Are