Problem accessing Lomonosov Tablebases

Discuss anything you like about chess related matters in this forum.
Post Reply
James Toon
Posts: 250
Joined: Fri Apr 06, 2007 5:54 pm
Location: Surrey

Problem accessing Lomonosov Tablebases

Post by James Toon » Fri Jan 21, 2022 3:20 pm

I'm not sure if this is the right board for this issue. I have come across a technical problem which I can't resolve online and wondered if anyone else had seen it.

I have signed up to play correspondence chess in this year's county championship. Part of the documentation says that claims of a forced win or draw with optimal play in positions with a reduced number of pieces will be decided with reference to Lomonosov 7-piece tablebases. These are a recent development and only seem to be available through the Windows database programs of a company called Chess OK. I bought and downloaded the latest version (Aquarium 2022). Because the tablebases are so large (about 140,000 Gb) they are accessed through an online server to which the program is supposed to connect. But when I try to connect I get the error message "Error 10061. No connection could be made because the target machine actively refused it." Online research suggests that this might relate to file corruption or the use of a firewall. But I've investigated these and they're not causing the problem. I have contacted Chess OK but no-one has got back to me.

User avatar
Jon Tait
Posts: 149
Joined: Sat Jul 25, 2009 8:31 am
Contact:

Re: Problem accessing Lomonosov Tablebases

Post by Jon Tait » Fri Jan 21, 2022 3:39 pm

Yes, there's something wrong at their end. I've used the Lomonosov tablebases quite a lot over the past few years and it's only recently they've started giving the Error message. No one seems to be sorting it out either, which is annoying. There are other seven-piece databases online, but they only say "win" or "draw"; Lomonosov always gave more details.
blog inspired by Bronstein's book, but using my own games: http://200opengames.blogspot.co.uk/

Ian Thompson
Posts: 3543
Joined: Wed Jul 02, 2008 4:31 pm
Location: Awbridge, Hampshire

Re: Problem accessing Lomonosov Tablebases

Post by Ian Thompson » Fri Jan 21, 2022 3:49 pm

If you have an Android device you should be able to access them for free using https://play.google.com/store/apps/deta ... omonosovtb.

Whether that'll fix the problem you report, I don't know, because I don't have any Android devices to install the app on.

NickFaulks
Posts: 8452
Joined: Sat Jan 02, 2010 1:28 pm

Re: Problem accessing Lomonosov Tablebases

Post by NickFaulks » Fri Jan 21, 2022 4:24 pm

Ian Thompson wrote:
Fri Jan 21, 2022 3:49 pm
If you have an Android device you should be able to access them for free using https://play.google.com/store/apps/deta ... omonosovtb.

Whether that'll fix the problem you report, I don't know, because I don't have any Android devices to install the app on.
Just tried the app on my phone, which I haven't looked at for ages. It says Connection Failed.
If you want a picture of the future, imagine a QR code stamped on a human face — forever.

Kevin Thurlow
Posts: 5802
Joined: Wed Apr 30, 2008 12:28 pm

Re: Problem accessing Lomonosov Tablebases

Post by Kevin Thurlow » Fri Jan 21, 2022 11:19 pm

Same problem if you try here https://www.iccf.com/message?message=641

Follow the link and people are grumbling it's not working. I thnk syzygy is though.

James Toon
Posts: 250
Joined: Fri Apr 06, 2007 5:54 pm
Location: Surrey

Re: Problem accessing Lomonosov Tablebases

Post by James Toon » Sat Jan 22, 2022 7:09 am

I took this up with the ICCF overnight. They confirmed that the syzygy route still works for positions with up to 7 pieces: go to https://syzygy-tables.info/.

Wadih Khoury
Posts: 604
Joined: Sun Jul 12, 2020 8:14 pm

Re: Problem accessing Lomonosov Tablebases

Post by Wadih Khoury » Sat Jan 22, 2022 9:39 am

Is there a technicality where you are not allowed to use a table base like the one on Lichess?
https://lichess.org/blog/W3WeMyQAACQAdf ... e-complete

I would assume that all table bases have the same outcome (win/draw/loss) but maybe different pathing to it?

Kevin Thurlow
Posts: 5802
Joined: Wed Apr 30, 2008 12:28 pm

Re: Problem accessing Lomonosov Tablebases

Post by Kevin Thurlow » Sat Jan 22, 2022 12:45 pm

"Is there a technicality where you are not allowed to use a table base like the one on Lichess?"

I assume the ones mentioned on ICCF site are the ones used. I made such a claim recently as an opponent clearly was not going to resign. The process was either automatic, or someone was hovering over the computer waiting for a claim and assessed it immediately. The Lichess one might work, all that happens if your claim is wrong is that you have to play the move (if any) you made when making the claim. (e.g. I intend to play Rf6 repeating the position for the third time.)

My opponent was very unhappy and sent me a long rant, complaining that the decision was wrong and I was unsporting to claim it anyway. In another game, the opponent played on Q+R down, until mated. Well, you've paid your entry fee, but nobody is going to mess that up at CC, unless they suffer a catastrophic internet failure for 6 weeks, or become seriously ill. The practical point of view from ICCF is that if you reach a tablebase ending, you are just going to play the tablebase moves, so why not just claim the result. I would add that the opponent was clearly using Stockfish (e.g.), but believing what it said after about 1 minute, rather than waiting to see if it changed its mind.

NickFaulks
Posts: 8452
Joined: Sat Jan 02, 2010 1:28 pm

Re: Problem accessing Lomonosov Tablebases

Post by NickFaulks » Sat Jan 22, 2022 12:55 pm

Kevin Thurlow wrote:
Sat Jan 22, 2022 12:45 pm
complaining that the decision was wrong
How can we be sure that there aren't any bugs in the new(ish) tablebases? If your opponent thought he had found one, I assume that could have been presented as evidence in an appeal and would have been of value to the whole community.
If you want a picture of the future, imagine a QR code stamped on a human face — forever.

User avatar
Christopher Kreuzer
Posts: 8781
Joined: Fri Aug 06, 2010 2:34 am
Location: London

Re: Problem accessing Lomonosov Tablebases

Post by Christopher Kreuzer » Sat Jan 22, 2022 1:00 pm

NickFaulks wrote:
Sat Jan 22, 2022 12:55 pm
Kevin Thurlow wrote:
Sat Jan 22, 2022 12:45 pm
complaining that the decision was wrong
How can we be sure that there aren't any bugs in the new(ish) tablebases? If your opponent thought he had found one, I assume that could have been presented as evidence in an appeal and would have been of value to the whole community.
Bugs in what sense? Incorrect calculation? Or a database glitch? (I think tablebases are not strictly speaking databases, though quite what they are, I am not sure. Tablebases, maybe?)

https://en.wikipedia.org/wiki/Endgame_tablebase

OK, they are still database, just very specialised ones.

Kevin Thurlow
Posts: 5802
Joined: Wed Apr 30, 2008 12:28 pm

Re: Problem accessing Lomonosov Tablebases

Post by Kevin Thurlow » Sat Jan 22, 2022 3:20 pm

"How can we be sure that there aren't any bugs in the new(ish) tablebases?"

A fair point, but I can modestly say that the tablebase confirmed my analysis in this case!

NickFaulks
Posts: 8452
Joined: Sat Jan 02, 2010 1:28 pm

Re: Problem accessing Lomonosov Tablebases

Post by NickFaulks » Sat Jan 22, 2022 6:43 pm

Christopher Kreuzer wrote:
Sat Jan 22, 2022 1:00 pm
Bugs in what sense?
In the sense that they say a position is a win with best play for both sides when it is in fact a draw.
If you want a picture of the future, imagine a QR code stamped on a human face — forever.

Wadih Khoury
Posts: 604
Joined: Sun Jul 12, 2020 8:14 pm

Re: Problem accessing Lomonosov Tablebases

Post by Wadih Khoury » Sun Jan 23, 2022 3:22 pm

Tablebases, by definition, are "solved" positions that engines may stlll get wrong.The only issue could be a bug in the software retrieving the database position.

Post Reply