Since you’re here...

We hope you will consider supporting us today. We need your support to continue to exist, because good entries are more and more work time. Every reader contribution, however big or small, is so valuable. Support "Chess Engines Diary" even a small amount– and it only takes a minute. Thank you.
============================== My email: jotes@go2.pl



Chess engine: Simbelmyne 1.9.0

 


Simbelmyne UCI engine  Author:Sam Roelants
Rating CEDR=2474 

v.1.9.0:
What's new
This version brings major improvements to the search (getting close to being a somewhat mature search!), and has seen a decent amount of work go into speeding up the underlying move generation.

Probably the bigger and more impactful change has been that I've set up a personal OpenBench instance, powered by 4 dedicated GCP workers. This has massively improved the speed and ergonomics of testing, and means I can finally test smaller improvements that would have been impossible until now.

You can find the OB instance at https://chess.samroelants.com, if you want a recorded history of my many failures, and sporadic successes!

Simbelmyne v1.9 is around 140 Elo stronger than v1.8 in STC self-play, and a small gauntlet places it at around 3114 Elo.

   # PLAYER              : RATING    POINTS  PLAYED    (%)
   1 Avalanche 1.4       : 3214.0     248.5     425   58.5%
   2 Black Marlin 4.0    : 3206.0     244.0     336   72.6%
   3 Nalwald 17          : 3199.0     281.0     425   66.1%
   4 Stash 30            : 3162.0     270.5     424   63.8%
   5 Princhess 0.16      : 3153.0     261.5     424   61.7%
   6 Koivisto 4.0        : 3138.0     194.0     425   45.6%
   7 Patricia 2.0        : 3135.0     249.5     424   58.8%
   8 Simbelmyne 1.9      : 3114.4    1939.0    4156   46.7%
   9 Avalanche 1.3       : 3085.0     160.5     425   37.8%
  10 Patricia 1.0        : 3053.0     146.5     424   34.6%
  11 Polaris 1.8.1       : 3052.0     161.0     424   38.0%

Added features
🔍 Search
PVS SEE Pruning (7.5 +/- 5.7) (#154)
2-ply conthist (11.89 +/- 6.84) (#236)
Clear next ply's killers (10.90 +/- 6.45) (#239)
Use improving in RFP (5.42 +/- 4.09) (#242)
Use improving in FP (5.43 +/- 4.10) (#245)
Add tactical history (19.86 +/- 9.10) (#244)
Singular extensions (9.14 +/- 5.80) (#250)
Double extensions (11.86 +/- 6.68) (#251)
4-ply conthist (5.40 +/- 4.07) (#252)
Use threat-based history (6.70 +/- 4.73) (#253)
⚖️: Evaluation
Use packed eval (22.7 +/- 15.2) (#233)
🐛 Bugfixes
Stop lmr reduction from overflowing (#241)
Clear conthist beteen games (#247)
Misc
Movegen refactor (13.7 +/- 10.7) (#235)
Speed improvements (19.7 +/- 13.7) (#234)
Generate quiets lazily (#227)
Lazily yield TT move before generating captures (22.8 +/- 15.2) (#225)
See the respective PRs for self-play results where relevant

Choosing a binary
This release comes with precompiled binaries for all major platforms. Because
the engine benefits tremendously from more modern CPU instruction sets, there
are binaries compiled for major instruction sets, following the x86-64
microarchitecture levels
as a naming scheme.

Realistically, on modern hardware (< 10 years old), you should be okay to use the
binaries labeled V3. If the engine crashes within the first seconds, try V2,
and so on.

What's Changed
Move "forced move" logic out of negamax by @sroelants in #224
Lazily yield TT Move from move picker by @sroelants in #225
Add helpers for generating tacticals and quiets separately by @sroelants in #226
Generate quiets lazily (17+/-??) by @sroelants in #227
Only store a single board of checkers by @sroelants in #228
Store threats bitboard on Board by @sroelants in #229
Sort killers in FIFO order by @sroelants in #230
is_legal helper by @sroelants in #231
Use packed eval by @sroelants in #233
Random speed improvements by @sroelants in #234
The great movegen rewrite by @sroelants in #235
Add SEE pruning by @sroelants in #154
Openbench preparations by @sroelants in #238
Add 2-ply conthist by @sroelants in #236
Clear the next ply's killers by @sroelants in #239
Stop lmr reduction from overflowing by @sroelants in #241
Search/improving rfp by @sroelants in #242
Simplify quiet history updates by @sroelants in #243
Add tactical history (19.86+/-9.10) by @sroelants in #244
Use improving in FP by @sroelants in #245
Singular extensions by @sroelants in #250
Double extensions by @sroelants in #251
Search/4 ply conthist by @sroelants in #252
Threat-based history by @sroelants in #253


Simbelmyne 1.8.0 - results:
Rustic-Knight 1.0.07/7+77 Games
Camel 1.6.06.5/7+67 Games
Simplex 0.9.8 JA6/6+66 Games
Spaghet Pesto 1.06/6+66 Games
Beast 15 MPV0.5/6-56 Games
Clover 6.20/6-66 Games
Lynx 1.5.04.5/5+45 Games
Princhess 0.17.02/5-15 Games
Odonata 0.9.01.5/5-25 Games
Wasp 7.001/5-35 Games
Obsidian 12.290/5-55 Games
Clarity 7.0.01/4-24 Games
Stockfish dev-202406081/4-24 Games
Steel Fighter 20.5/4-34 Games
Little Beast 150.5/4-34 Games
Lc0 0.31.0-rc30.5/4-34 Games
Titan 1.1.00.5/4-34 Games
SF-PRO 10.06.20240/4-44 Games
CorChess dev-202406060/4-44 Games
PlentyChess 2.0.00/4-44 Games
Marauders 3.60/4-44 Games

Simbelmyne 1.9.0 download


Comments