Search found 64 matches

by ymatioun
Wed Feb 03, 2016 10:39 pm
Forum: Computer Chess Club: General Topics
Topic: Fizbo 1.6 released
Replies: 22
Views: 5420

Re: Fizbo 1.6 released

No, no 32 bit version.

All the code has been based on 64 bit data structures from day 1.

Youri.
by ymatioun
Sun Jan 31, 2016 6:35 pm
Forum: Computer Chess Club: General Topics
Topic: Fizbo 1.6 released
Replies: 22
Views: 5420

Re: Fizbo 1.6 released

OK, i found the problem and fixed it. Corrected executables are uploaded to my site (https://sites.google.com/site/fizbochessengine/). The problem was that i accidentally removed code that verifies that SYZYGY files are in place before using them. As a result, engine tried to open files that don't e...
by ymatioun
Sun Jan 31, 2016 1:28 pm
Forum: Computer Chess Club: General Topics
Topic: Fizbo 1.6 released
Replies: 22
Views: 5420

Re: Fizbo 1.6 released

I will look into time losses right away.

About +90 ELO on 4 cores: this is difference in playing strength between fizbo 1.6 running on 1 CPU core and fizbo 1.6 running on 4 CPU cores. Many top programs show larger increase 1 CPU vs 4 CPU.

Youri.
by ymatioun
Fri Jan 15, 2016 10:59 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: test positions for texel tuning
Replies: 32
Views: 6073

Re: test positions for texel tuning

Gradient descent can be fast if you capture evaluation weights during call to evaluate(). Those are weights that are multiplied by coefficients and summed up to get the evaluation. (this only works for linear evaluation functions) Then after one pass through Qsearch() you can construct full correlat...
by ymatioun
Thu Nov 12, 2015 12:49 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: pieces psqt
Replies: 5
Views: 1931

Re: pieces psqt

i do use separate PST value for each square, with left-right symmetry. So that each piece gets 32 values. This works well with automatic coefficient generation, with exception of king mid-game, where there are just not enough situations where king is away from its starting position.

Youri.
by ymatioun
Mon Sep 14, 2015 10:17 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: atomic TT
Replies: 56
Views: 7305

Re: atomic TT

what i do in Fizbo is i keep TT entry within one 8 byte block, which can be accessed atomically. Here is my declaration of main TT entry: // main transposition table data structure typedef struct{ unsigned short int lock2; // 2 bytes of lock = 16 bits unsigned char lock1; // 1 more byte of lock =24 ...
by ymatioun
Tue Sep 08, 2015 12:07 pm
Forum: Computer Chess Club: Tournaments and Matches
Topic: Fizbo 1.5 (29Aug2015) syzygy problems, again!
Replies: 21
Views: 2125

Re: Fizbo 1.5 (29Aug2015) syzygy problems, again!

I'll see if i can find a reason for this and fix it. In my testing i have not seen any timeouts. But my testing was at shorter time controls.

Youri.
by ymatioun
Mon Sep 07, 2015 12:17 pm
Forum: Computer Chess Club: Tournaments and Matches
Topic: Fizbo 1.5 (29Aug2015) syzygy problems, again!
Replies: 21
Views: 2125

Re: Fizbo 1.5 (29Aug2015) syzygy problems, again!

I will see if i can change this for the next release. But for now there is not much i can do, so just run Fizbo without tablebases. I don't think this would impact performance by much.

Youri.
by ymatioun
Sun Sep 06, 2015 2:49 pm
Forum: Computer Chess Club: Tournaments and Matches
Topic: Fizbo 1.5 (29Aug2015) syzygy problems, again!
Replies: 21
Views: 2125

Re: Fizbo 1.5 (29Aug2015) syzygy problems, again!

Right. that is what i would do - try it in console. At start-up it looks in directories specified in environment variables DTZDIR and WDLDIR. And on command "SyzygyPath" it looks at all the directories supplied. One limitation that i know of: i only tested it with all syzygy files located in one dir...
by ymatioun
Thu Aug 20, 2015 10:03 pm
Forum: Computer Chess Club: General Topics
Topic: Fizbo 1.5 released
Replies: 18
Views: 4402

Re: Fizbo 1.5 released

No, only 5 and fewer.