catalinfrancu/colibri

An antichess engine with bitboards, 5-man endgame tables and proof number search.

colibri's Issues

Allow deleting solved subtrees

Some parts of e3 Nf6 are slow

Some calls to PN1 in e3 Nf6 are very slow (~10 seconds). This could be due to the number of EGTB calls. Log the number of EGTB calls to make sure.

Better monitoring

Don't look for online:true, which is flaky. Look for something like "active X seconds ago".

Resources available should be checked outside expand()

Currently we check inside expand() that there are at least 10,000 nodes/edges available. That's because sometimes we need a lot of resources for cascading depth updates. The check should be performed somewhere outside expand(), because expand() itself doesn't need many nodes.

Show more information in node browser

• Link to root node (starting position if that's what the book is for, but possibly another position).
• Moves played from root node to current position (show up to N paths if multiple paths exist).
• Subtree size.
• Ability to collapse a node (into a 1/1 leaf).

These apply to the node browser. Figure out what to do when the current position is not from the book, but from the endgame tables.

index.php should resport the port defined in colibri.conf

Optimization ideas

• Keep each node's children sorted by proof numbers.
• Speed up finding the MPN. If update() stops early at some node u, then start at u next time we select the MPN.
• Cache some boards (including their Zobrist keys) in nodes so that we don't need to keep making moves starting from the top.
• Dynamic sizing of the second-level search.
• Stop transferring children from PN1 to PN2 if the first transferred child loses.

Ability to complete proofs

Once an opening is solved, there should be an ability to expand winning nodes all the way to victory. By default, the book stops at nodes provable with a short PN search.