Search found 17051 matches

by bob
Fri Apr 24, 2020 1:34 am
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Crafty 25.6 without Syzygy
Replies: 1
Views: 333

Re: Crafty 25.6 without Syzygy

I made these changes. Had forgotten to do that when I added the SYZYGY code...
by bob
Fri Apr 24, 2020 1:20 am
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Crafty 25.6 search stability
Replies: 39
Views: 4883

Re: Crafty 25.6 search stability

So it is possible that the hash/memory is being shared between all running Craftys? Something changes... Another good example would be the historical Crafty benchmark. Bob would have the official total nodes number. The only thing that would change is the total time elapsed and NPS. All of the rest...
by bob
Fri Apr 24, 2020 12:53 am
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Crafty 25.6 search stability
Replies: 39
Views: 4883

Re: Crafty 25.6 search stability

This is probably related: You have 4 programs. Crafty A, B, C, & D. Open Crafty A, type "analyze". Let it get to 'x' depth and then "exit" to stop analysis. Open Crafty B, type "analyze". Let it get to 'x' depth and then "exit" to stop analysis. The resulting output will be the same for both progra...
by bob
Fri Apr 24, 2020 12:50 am
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Crafty 25.6 search stability
Replies: 39
Views: 4883

Re: Crafty 25.6 search stability

This is probably related: You have 4 programs. Crafty A, B, C, & D. Open Crafty A, type "analyze". Let it get to 'x' depth and then "exit" to stop analysis. Open Crafty B, type "analyze". Let it get to 'x' depth and then "exit" to stop analysis. The resulting output will be the same for both progra...
by bob
Thu Apr 23, 2020 2:42 am
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Crafty 25.6 search stability
Replies: 39
Views: 4883

Re: Crafty 25.6 search stability

I will look. If anything, I would suspect the PV is wrong, but the score is right. I don't know that I clear the "PV hash table" where I store PV's that go with EXACT table hash entries. I am looking and don't see where that is done. I will look further and comment in a bit... OK, I looked. Here's w...
by bob
Mon Apr 20, 2020 9:29 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Allowing null move pruning in the endgame.
Replies: 5
Views: 597

Re: Allowing null move pruning in the endgame.

Most have done so. A good test is fine#70. Try it with and without your change. Null-move really fails when zugzwang is present. Because not having to move is a REAL advantage in such positions. If, by endgame, you mean something more than positions with no pieces present, that is problematic. If pi...
by bob
Fri Apr 17, 2020 10:23 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Compiler Optimization Question
Replies: 27
Views: 1675

Re: Compiler Optimization Question

I know even more. I developed code when there WAS no profiler or debugger except for me. :)

Those were really fun days...
by bob
Wed Apr 15, 2020 12:40 am
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Compiler Optimization Question
Replies: 27
Views: 1675

Re: Compiler Optimization Question

One more note for profiling. Profile the code you are going to run... the complete chess engine. Don't take a snippet, rewrite it in a way you think might be faster, then just profile the two snippets with a simple driver program. That can be highly misleading since you are not executing all the oth...
by bob
Mon Apr 13, 2020 5:01 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Compiler Optimization Question
Replies: 27
Views: 1675

Re: Compiler Optimization Question

Here's the simple answer from a compiler guy. Small functions are just fine. If they SHOULD be inlined, the compiler will do it during the compilation process. If it won't help, it won't. Not inlining can improve cache efficiency if the function is executed infrequently. Better to have the natural ...
by bob
Mon Apr 13, 2020 4:55 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: if statement and calculation faster than constant
Replies: 43
Views: 2390

Re: if statement and calculation faster than constant

Also, the speed progression from the time I started up until now (with reports split over several threads in this forum, on different subjects...) Perft 7, starting position: 277 seconds (superfluous memory allocation -> replace with move list pool) 114 seconds (start optimization rounds here..., s...