Stockfish 1.7.1 update available

[Tord Romstad]

I have now prepared a GUI release of Stockfish 1.7.1 for Mac OS X. Before uploading it to the Stockfish web site, I would like to have some independent confirmation that it works. Please download from this URL:

http://www.mediafire.com/?yzjyz3dingu

Before you get too excited, this is still only the old and amateurish Glaurung GUI, with a few minor changes. I have to start working on a new and more polished GUI some day.

The binary probably requires Mac OS 10.6, but might also work in 10.5. It certainly won't work in 10.4. It currently doesn't support PowerPC CPUs (I'll add that later if anyone is still interested), but should work on both 32-bit and 64-bit Intel CPUs. I'd appreciate if those among you who own an Intel Mac running 10.5 or newer could download the GUI and check if it works for you.

There is also one very minor difference in the engine code compared to the stand-alone 1.7.1 engine: If the engine detects 8 CPUs, it will assume that it is running on a quad with hyperthreading, and will use 4 threads by default. This is because quad-core iMacs are probably far, far more common than the outrageously expensive 8-core Mac Pros.

[Aaron Becker]

I have now prepared a GUI release of Stockfish 1.7.1 for Mac OS X. Before uploading it to the Stockfish web site, I would like to have some independent confirmation that it works. Please download from this URL:

http://www.mediafire.com/?yzjyz3dingu

Before you get too excited, this is still only the old and amateurish Glaurung GUI, with a few minor changes. I have to start working on a new and more polished GUI some day.

The binary probably requires Mac OS 10.6, but might also work in 10.5. It certainly won't work in 10.4. It currently doesn't support PowerPC CPUs (I'll add that later if anyone is still interested), but should work on both 32-bit and 64-bit Intel CPUs. I'd appreciate if those among you who own an Intel Mac running 10.5 or newer could download the GUI and check if it works for you.

There is also one very minor difference in the engine code compared to the stand-alone 1.7.1 engine: If the engine detects 8 CPUs, it will assume that it is running on a quad with hyperthreading, and will use 4 threads by default. This is because quad-core iMacs are probably far, far more common than the outrageously expensive 8-core Mac Pros.

The GUI itself all works under 10.5, but the stockfish binary you bundled only works under 10.6 due to a change in the way the loader works. After replacing that binary with one I compiled myself, everything looks like it's working perfectly. If you want to use a system running 10.6 to compile a stockfish binary that's compatible with 10.5, you just need to add the following flag when compiling (assuming your SDK is in the default location):

Code: Select all

--sysroot=/Developer/SDKs/MacOSX10.5.sdk

Congratulations on a great engine; it's inspiring to see how effective your open approach has been. I've certainly learned a lot from your code, and I'm very happy that such a strong and well-written engine is available for anyone to learn from.

[Frank Quisinsky]

Hi Tord, Joona, Marco and Jim,

thanks again for Stockfish 1.7.1 JA.
Great improvements.

I tested so far version 1.7.1 JA in SWCR Blitz.
In SWCR main rating list I will add SF 1.7.1 JA in around 7 days.

Very interesting could be that it's possible that Stockfish 1.7.1 is the new number 1 with 32-Bit.

Crazy:
After the first 14 games in round robin against 30 different opponents Stockfish lost 1 game only and won 13. The game Stockfish lost was against Glaurung 2.2

Now after 92 of 600 games = 80,43% and 1.5 : 1.5 vs. Glaurung 2.2 JA. Fantastic results.

Stockfish played now 3 games against The TOP 30. Best result for the others is 1.5 : 1.5 (against 4 engines). Great games, nice playing style.

All in all ...
I have so many fun ... THANKS again !!

Best
Frank

[schlucke]

I have now prepared a GUI release of Stockfish 1.7.1 for Mac OS X. Before uploading it to the Stockfish web site, I would like to have some independent confirmation that it works. Please download from this URL:

http://www.mediafire.com/?yzjyz3dingu

Before you get too excited, this is still only the old and amateurish Glaurung GUI, with a few minor changes. I have to start working on a new and more polished GUI some day.

The binary probably requires Mac OS 10.6, but might also work in 10.5. It certainly won't work in 10.4. It currently doesn't support PowerPC CPUs (I'll add that later if anyone is still interested), but should work on both 32-bit and 64-bit Intel CPUs. I'd appreciate if those among you who own an Intel Mac running 10.5 or newer could download the GUI and check if it works for you.

There is also one very minor difference in the engine code compared to the stand-alone 1.7.1 engine: If the engine detects 8 CPUs, it will assume that it is running on a quad with hyperthreading, and will use 4 threads by default. This is because quad-core iMacs are probably far, far more common than the outrageously expensive 8-core Mac Pros.

Thanks Tord, works fine here on my old MacBook Pro (Core2 Duo) with 10.6.3. Is the sf171 compile on optimized ICC build or GCC?

BTW: The new Icon is great

Bye,
Holger

[IWB]

Hello Tord,

I would like to emphasize that although this version is supposed to be functionally equivalent to 1.7 with the default settings, there is one little issue to be aware of:

As explained above, this version reverts to the 1.6.3 code for detecting the number of CPU cores. This means that it doesn't choose the right number of threads by default on CPUs with hyperthreading, like my Core i7 iMac. If Stockfish doesn't detect the correct number of CPU cores on your machine, it is important not only to adjust the number of search threads, but also the "Minimum Split Depth" parameter. On a CPU with 4 or fewer cores, this parameter should be set to 4. On an eight-core machine, it should be set to 7.

Sorry, but now it seems there is a certain mess starting.

I played 1800 games and got a rating.
Then 1.7.1 was released with the info that with Zugzwang ON it might differ 1-2 Elo.
I played 300 games (Zugzwang on), checked the Elo, and where actually 3 elo below the 1800 set.
I decided this is noise, substituded the engine and got a new rating with 2100 games. (-1 Elo)
Right now I play 500 games with ONE thread with Stockfish 1.7.1 but of course I did not change the minimum split depth (and I havent for the 300 first test games).

Am I supposed to do it or not? Do I have to play all again ...

Thx and Bye
Ingo

[IWB]

Hi

I have measured the impacted nodes and is less then 1% of cases....but real games results seem to show another story and we have to better analyze it,

Does this mean you expect more than 1-2 Elo difference when Zugzwang Detection is set to ON. And what about this from Tord:"but also the "Minimum Split Depth" parameter. On a CPU with 4 or fewer cores, this parameter should be set to 4." What happens if someone play Zugzwang detection ON, 1 Thread but leaves the Minimum split depth at 7? WHAT is the correct setting where you think it will give the best result, so what is to be considered as default?

I would appreciate a NEW thread, where someone of you collect all infos into ONE post so that a tester can rely on something.

I am too fast! For now I stop all testing and wait a bit until this "issue" is settled.

Bye
Ingo

[IWB]

Hello Tord,

I would like to emphasize that although this version is supposed to be functionally equivalent to 1.7 with the default settings, there is one little issue to be aware of:

As explained above, this version reverts to the 1.6.3 code for detecting the number of CPU cores. This means that it doesn't choose the right number of threads by default on CPUs with hyperthreading, like my Core i7 iMac. If Stockfish doesn't detect the correct number of CPU cores on your machine, it is important not only to adjust the number of search threads, but also the "Minimum Split Depth" parameter. On a CPU with 4 or fewer cores, this parameter should be set to 4. On an eight-core machine, it should be set to 7.

Sorry, but now it seems there is a certain mess starting.

I played 1800 games and got a rating.
Then 1.7.1 was released with the info that with Zugzwang ON it might differ 1-2 Elo.
I played 300 games (Zugzwang on), checked the Elo, and where actually 3 elo below the 1800 set.
I decided this is noise, substituded the engine and got a new rating with 2100 games. (-1 Elo)
Right now I play 500 games with ONE thread with Stockfish 1.7.1 but of course I did not change the minimum split depth (and I havent for the 300 first test games).

Am I supposed to do it or not? Do I have to play all again ...

Thx and Bye
Ingo

OK, I think everything is right. ALL my computer have a Minimum Spilt Depth of 4 as I switch off HT by default and the Q6600 have it on 4 automaticaly of course! I assume that my testing was correct then ... right?

Bye
Ingo

[mcostalba]

OK, I think everything is right. ALL my computer have a Minimum Spilt Depth of 4 as I switch off HT by default and the Q6600 have it on 4 automaticaly of course! I assume that my testing was correct then ... right?

Yes, it is correct, but as clearly stated in the 1.7.1 announcement zugdetection is OFF by default and should remain OFF for offcial testing.

What probably was not clearly stated is that when you turn ON zugdetection the progam _could_ become weaker, not stronger.

So zugdetection is good for analysis or for study on some position, but on real games, at the moment, we suggest to turn it OFF.

IOW, please test 1.7.1 AS IS ! Do not change anything because default setup is the strongest.

I hope this is clear enough.

[Eelco de Groot]

Hello Tord,

I would like to emphasize that although this version is supposed to be functionally equivalent to 1.7 with the default settings, there is one little issue to be aware of:

As explained above, this version reverts to the 1.6.3 code for detecting the number of CPU cores. This means that it doesn't choose the right number of threads by default on CPUs with hyperthreading, like my Core i7 iMac. If Stockfish doesn't detect the correct number of CPU cores on your machine, it is important not only to adjust the number of search threads, but also the "Minimum Split Depth" parameter. On a CPU with 4 or fewer cores, this parameter should be set to 4. On an eight-core machine, it should be set to 7.

Sorry, but now it seems there is a certain mess starting.

I played 1800 games and got a rating.
Then 1.7.1 was released with the info that with Zugzwang ON it might differ 1-2 Elo.
I played 300 games (Zugzwang on), checked the Elo, and where actually 3 elo below the 1800 set.
I decided this is noise, substituded the engine and got a new rating with 2100 games. (-1 Elo)
Right now I play 500 games with ONE thread with Stockfish 1.7.1 but of course I did not change the minimum split depth (and I havent for the 300 first test games).

Am I supposed to do it or not? Do I have to play all again ...

Thx and Bye
Ingo

OK, I think everything is right. ALL my computer have a Minimum Spilt Depth of 4 as I switch off HT by default and the Q6600 have it on 4 automaticaly of course! I assume that my testing was correct then ... right?

Bye
Ingo

Hi Ingo,

I think everything with your tests should be okay. The split depth you can ignore because its only function is to determine where to start a new thread in the search tree, and you are testing with only a single core so the code is never used. The Zugzwang ON seems to confirm the programmers guess that the difference would be hard to measure and your result is, within the uncertainty margins, the same.

Regards, Eelco

[Uri Blass]

OK, I think everything is right. ALL my computer have a Minimum Spilt Depth of 4 as I switch off HT by default and the Q6600 have it on 4 automaticaly of course! I assume that my testing was correct then ... right?

Yes, it is correct, but as clearly stated in the 1.7.1 announcement zugdetection is OFF by default and should remain OFF for offcial testing.

What probably was not clearly stated is that when you turn ON zugdetection the progam _could_ become weaker, not stronger.

So zugdetection is good for analysis or for study on some position, but on real games, at the moment, we suggest to turn it OFF.

IOW, please test 1.7.1 AS IS ! Do not change anything because default setup is the strongest.

I hope this is clear enough.

I do not understand how do you know that default setup is the strongest.

There are many parameters that people can change and people may find stronger setting espacially when you tested only at fast time control and it is possible that some different setting is stronger at slower time control and not at faster time control.

Uri