Houdini 6 and Syzygy

Discussion of anything and everything relating to chess playing software and machines.

Moderators: bob, hgm, Harvey Williamson

Forum rules
This textbox is used to restore diagrams posted with the [d] tag before the upgrade.
Post Reply
Posts: 123
Joined: Sat Feb 04, 2017 10:57 pm
Location: USA

Houdini 6 and Syzygy

Post by MOBMAT » Thu Feb 13, 2020 6:17 pm

I found a few positions that Houdini 6 can't solve when Syzygy tables are enabled.
Conditions are H6 Pro, 16384Mb hash, 4 threads, Tactical mode (makes no difference), Syzygy on, Nalimov (on or off)
Syzygy Probe Depth 20 (default)

I verified the checksums of the Syzygy files.

This is a mate in 10, but H6 maxes out depth 99 and says M11.

If I disable Syzygy, and try it without any EGTB or with just Nalimov enabled, it finds it easily.

Here is another, a mate in 9. H6 reports a Syzygy winning score (+148.96), but never resolves the mate.

Any ideas what is happening here?
Vince S
Author of MOBMAT

"Reductions, extensions, and pruning, oh my!"

Post Reply