Toga II 4.0 release

[jd1]

Dear all,

Happy New Year! It is my pleasure, after a break of several years from computer chess, to release Toga II 4.0.

Strength

Self-play results:
+80 elo at 4' + 0.04' on 1 thread after 4000 games
+85 elo at 10' + 0.1' on 4 threads after 2000 games

So while I doubt the rating lists will show +80 elo it should be significantly stronger than Toga II 3.0 or any other Fruit derivative and also one of the strongest array-based engines in the world. Needless to say, Stockfish and the other top engines still smash it though ...

Compiles

- The IntelPGO compiles should be the fastest. However, if there are any problems, GCC and Intel non-PGO compiles are also provided.
- The x64 compile runs about 10% faster than the w32 compile on my machines.
- At this stage I do not have Linux, Mac or Android compiles. Hopefully someone will provide these at some stage.

Major changes

For a full list of changes since Toga II 3.0, see readme.txt in the package. The major changes are:
- code tidy-up, removed a lot of unused / defunct code and fixed a few bugs.
- Toga II can now use up to 16 GB hash and up to 64 threads, and the lazy SMP design has been tweaked.
- fixed aspiration windows, and skip fail-high research for single-thread competitive games (same patch as SF tested a day ago).
- removed egbb support. Instead I plan to add support for Ronald De Man's excellent syzygy bases for future releases.
- added eval pruning (also called static null move pruning), and move count based pruning;
- improved null move: reduction (3 + depth/4) from Stockfish used, and double null move avoided;
- better usage of hash in quiescent search;
- bad captures reduced less;
- history aging.

Have fun!

Jerry

[Graham Banks]

That is a nice surprise!
Thanks.

[Damir]

Thanks Jerry. You are doing an amazing work so far.

[Ovyron]

Wow, I assumed this project was dead, or something. Thanks!

BTW, does anybody know why is it called Toga II? I had expected to see a Toga III eventually, but it seems it'll follow II x.0... numeration.

[BrendanJNorman]

Wow, I assumed this project was dead, or something. Thanks!

BTW, does anybody know why is it called Toga II? I had expected to see a Toga III eventually, but it seems it'll follow II x.0... numeration.

Will we see a new Checkov version you think?

[jd1]

Wow, I assumed this project was dead, or something. Thanks!

BTW, does anybody know why is it called Toga II? I had expected to see a Toga III eventually, but it seems it'll follow II x.0... numeration.

Thomas Gaksch decided to put the II in and it's stayed since.

I guess one day I should make it Toga III ... maybe next version

[jpqy]

Wow Jerry ,this is indeed a very nice surpise

Tested Toga for so many years with Misha all these versions..always thought you will come back one day..ones bitten and addicted to chess they say these kind off people you see back!

This is nice..will be sure on my do to list..

Wish you a nice end years holdidays..

Best regards,
Jean-Paul.

[tomitank]

I'm very happy! I like Toga! I learned a lot from it.
Thank you Donald!

-Tamás

[Dokterchen]

A nice belated Christmas gift. Thanks Jerry.

[Ovyron]

Will we see a new Checkov version you think?

The real question is if Toga II sacrificed style for improving its strength!

I recall that back when Toga II 3.1.2SE Chekov was released, there were stronger Togas around, but wouldn't plays as attractive with these settings (or, am I hallucinating, apparently II 3.1.2SE was released in 2008, while II 2.0 was released on 2012 o_O), so maybe it's like Rybka, that had her style going downhill after version 3.

What we need is a tool to measure the engine style, with a pieces en prise, sacrifices and so on, to end with such speculation