Thinker 5.4 2CPU <-> Thinker 5.4 4CPU

[Werner]

In my tests I have problems to see the advantage of 4CPU with Thinker 5.4. Here is one example I made using the same openings in eng-eng matches without pondering (for CEGT 40/20)

Code: Select all

1   Thinker 5.4 Ai x64 4CPU    2200  +12/-11/=27 51.00%   25.5/50 
2   Fruit 2.3.5m x64 2CPU p15  2200  +11/-12/=27 49.00%   24.5/50

Code: Select all

1   Thinker 5.4Ai x64 2CPU     2200  +17/-11/=22 56.00%   28.0/50 
2   Fruit 2.3.5m p15 w32 2CPU  2200  +11/-17/=22 44.00%   22.0/50 

The 2CPU version scored better against the slightly stronger 32bit version of Fruit.

[ernest]

Hi Werner,
How about (My God, NOOO!!!) an informal (yes , INFORMAL!!!, that can't be serious) match Thinker 5.4 2CPU against Thinker 5.4 4CPU, just to check...

[Werner]

Hi Werner,
How about (My God, NOOO!!!) an informal (yes , INFORMAL!!!, that can't be serious) match Thinker 5.4 2CPU against Thinker 5.4 4CPU, just to check...

Hi Ernest,

no!


...I hope Kerwin read this message and makes such a match...

[Norm Pollock]

I'm not a believer in intra-family matches (matches between different versions of the same engine). These matches tend to have an increased number of draws because the same basic engine does not "see" a weak position of its family member as often as another engine would. The intra-family matches can be boring and not as meaningful as inter-family matches.

[CThinker]

In my tests I have problems to see the advantage of 4CPU with Thinker 5.4. Here is one example I made using the same openings in eng-eng matches without pondering (for CEGT 40/20)

Code: Select all

1   Thinker 5.4 Ai x64 4CPU    2200  +12/-11/=27 51.00%   25.5/50 
2   Fruit 2.3.5m x64 2CPU p15  2200  +11/-12/=27 49.00%   24.5/50

Code: Select all

1   Thinker 5.4Ai x64 2CPU     2200  +17/-11/=22 56.00%   28.0/50 
2   Fruit 2.3.5m p15 w32 2CPU  2200  +11/-17/=22 44.00%   22.0/50 

The 2CPU version scored better against the slightly stronger 32bit version of Fruit.

The "threads" option in Thinker is the number of search threads. However, Thinker has a master thread for monitoring the search. This means that when you specify 4 threads, there are actually 5 active threads. If your machine only has 4 CPUs, this would be really bad.

I suggest that you try "threads=3" if your machine only has 4 CPUs.

Also, the parallel search code is currently being overhauled by Kerwin. We should see better scaling in the next release.

Cheers...

[Dr.Wael Deeb]

In my tests I have problems to see the advantage of 4CPU with Thinker 5.4. Here is one example I made using the same openings in eng-eng matches without pondering (for CEGT 40/20)

Code: Select all

1   Thinker 5.4 Ai x64 4CPU    2200  +12/-11/=27 51.00%   25.5/50 
2   Fruit 2.3.5m x64 2CPU p15  2200  +11/-12/=27 49.00%   24.5/50

Code: Select all

1   Thinker 5.4Ai x64 2CPU     2200  +17/-11/=22 56.00%   28.0/50 
2   Fruit 2.3.5m p15 w32 2CPU  2200  +11/-17/=22 44.00%   22.0/50 

The 2CPU version scored better against the slightly stronger 32bit version of Fruit.

The "threads" option in Thinker is the number of search threads. However, Thinker has a master thread for monitoring the search. This means that when you specify 4 threads, there are actually 5 active threads. If your machine only has 4 CPUs, this would be really bad.

I suggest that you try "threads=3" if your machine only has 4 CPUs.

Also, the parallel search code is currently being overhauled by Kerwin. We should see better scaling in the next release.

Cheers...

Thanks Lance for the clarification

[Werner]

The "threads" option in Thinker is the number of search threads. However, Thinker has a master thread for monitoring the search. This means that when you specify 4 threads, there are actually 5 active threads. If your machine only has 4 CPUs, this would be really bad.

I suggest that you try "threads=3" if your machine only has 4 CPUs.

Also, the parallel search code is currently being overhauled by Kerwin. We should see better scaling in the next release.

Cheers...

Hi Lance,
thank´s for the answer. What you say confuses me and sure other tester too
a) when I set threads to 3 and it is Thinker´s turn then only 75% of the quad Cpu ís used!! So normally I use threads = 4. And this is the same with all other engines I have!!
b) There are other engines here where I can see they are using more threads than the PC has cpus - and there is no real problem.

So I think there is more or less a problem with the engine using 4CPUs and hopefully Kerwin has a solution.

Best

[ernest]

I suggest that you try "threads=3" if your machine only has 4 CPUs.

So what should I do with a 2-core machine?

[Dr.Wael Deeb]

I suggest that you try "threads=3" if your machine only has 4 CPUs.

So what should I do with a 2-core machine?

Logicaly thinking,you should use a thread and a half

[rainhaus]

In my tests I have problems to see the advantage of 4CPU with Thinker 5.4. Here is one example I made using the same openings in eng-eng matches without pondering (for CEGT 40/20)

Code: Select all

1   Thinker 5.4 Ai x64 4CPU    2200  +12/-11/=27 51.00%   25.5/50 
2   Fruit 2.3.5m x64 2CPU p15  2200  +11/-12/=27 49.00%   24.5/50

Code: Select all

1   Thinker 5.4Ai x64 2CPU     2200  +17/-11/=22 56.00%   28.0/50 
2   Fruit 2.3.5m p15 w32 2CPU  2200  +11/-17/=22 44.00%   22.0/50 

The 2CPU version scored better against the slightly stronger 32bit version of Fruit.

Hi Werner
thus they are, the testers For the sake of selectivity and for their lists they play 1000 of games and more,- with each engine of course-, but to interpret a difference of only 5% there suddenly 50 games should be enough. Non ,non Messieurs, a sample of 50 games/match is too small for realizing a significance between 51% and 56% of scoring. There are statistical formulas to calculate the necessary size of a sample, please. You need about 400 games between Fruit / Thinker2CPU and also 400 games between Fruit / Thinker4CPU to test for the 95% level of significance! Based on these two matches you can interpret nothing, whatever engine scores better or worse.
Surly, an experienced Engine Tester sometimes feels instinctively, that there might be something a bit fishy. In this case it’s better to search for bugs, incorrect using, or ask the programmer. This may be more useful than generating a huge cemetery of games.
mfg Rainer