Chess engine: Drofa 4.1.1 JA (Windows and Linux)

 

Drofa - UCI chess engine (written in C++11), Author: Alexander Litov.
Rating Chess Engines Diary CEDR=3285

Drofa started as fork of the Shallow Blue chess engine. 

v.4.1.1:

Drofa v4.1.1 64 ja

Windows/Linux clang profiled builds 

Major gainers:

Tuning of the pre-move-loop pruning

SEE rewrite, in accordance to what is used in top engines

Using ALPHA cutoffs in the TT

SPSA of the incremental TM (big thanks for AGE for implementing SPSA for openbench)

Rewriting TT allocation and probing

Regression on the Pohl.pgn book

Elo   | 51.91 +- 3.55 (95%)

Conf  | 40.0+0.40s Threads=1 Hash=64MB

Games | N: 20000 W: 6892 L: 3926 D: 9182

Penta | [150, 1510, 4217, 3470, 653]

You can expect much less elo on a balanced books and/or while using non-incremental TM

As per usual, choose the binary with best speed, but building using make should give a better binary

Drofa 4.1.0 - results:

Mida 2.3	10/17	+3	17 Games
Protej 20231212a	11.5/15	+8	15 Games
Cool Iris 11.80	0.5/15	-14	15 Games
Obsidian 9.0	0/15	-15	15 Games
Stormphrax 4.0.0	1.5/14	-11	14 Games
Lynx 1.1.0	12.5/13	+12	13 Games
RukChess 3.0.18	6/13	-1	13 Games
Pedantic 0.6.0	8/11	+5	11 Games
Knightx 3.9	9.5/10	+9	10 Games
Princhess 0.15.1	9/10	+8	10 Games
TACTICAL 161223	1.5/9	-6	9 Games
Incognito 5	0.5/8	-7	8 Games
Vividmind 1.0	6/6	+6	6 Games
Lxna 0.3.1	6/6	+6	6 Games
Zagreus 4.0	6/6	+6	6 Games
Austerlitz 1.4.7	5.5/6	+5	6 Games
LTChess 9.3	4/6	+2	6 Games
Alexandria 5.1.0	1/6	-4	6 Games
Clover 6.1	0.5/6	-5	6 Games
CorChess 20231219	0.5/6	-5	6 Games
YuliGM PrO 15	0/6	-6	6 Games

Drofa 4.1.1 JA - downloadDrofa 4.1.1 JA - download