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Normal Topic When does CB 14 display all tablebase moves? (Read 749 times)
ReneDescartes
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When does CB 14 display all tablebase moves?
03/17/17 at 02:03:23
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I am baffled by Chessbase 14's behavior when using Syzygy tablebases to analyze a position like this, from Dvoretsky's Endgame Manual, Illustrative Position 9-7 (I think Tarrasch first analyzed it):

* * * * * * * *
* * * * * * * *
* * * * * * * *
* * * * * * * *
* * * * * * * *
* * * * * * * *
* * * * * * * *
* * * * * * * *
*

All the positions are in the tablebase. Yet CB14 sometimes displays a simple evaluation and one line but not the tablebase's complete list of moves, whereas at other times it displays the tablebase's list of moves, which I prefer, but not a line.

For example, after 1.Ke6 Ra6+ CB displays one long drawing line (with multi-PV set to one variation), though Black has 16 legal moves. After the further moves 2.Ka5 Ra5+ 3.Rd5, however, when Black again has exactly 16 legal moves, it displays instead of a variation, the table of all 16 possible move, again with multi-PV set to one.

This is Komodo 10.3 on Windows 10, with the engine parameters set as follows: Syzigy probe depth=2 (the default, in order to consult tablebases early in the search rather than waiting for deeper levels; the same happens when this is set to 1 or 0); Syzigy probe limit = 6 (trigger the TB search with 6 pieces on the board, also default); smart Syzigy (conserve physical hard-disk use) off, since I have the whole 3-4-5-6 TB on SSD; and 50-move limit on. I use a hash of 6144 or 3072 MB out of 16 GB RAM, but the same happens with 2048; and threads is set to 3. I ran MD5 checksums on the rook and pawn databases and the Syzygy tables are not corrupted.

I get similar results with Stockfish.

Can anyone tell me how to get the full list of moves and their TB evaluations whenever a position is in the TB?
« Last Edit: 03/18/17 at 00:33:31 by ReneDescartes »  
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