Toga and 64 bit(and a few other questions)

[revengeska]

A few questions about Toga:

1. How come none of the rating lists use 64 bit Toga? The source is there, so it shouldn't be too hard to compile it(I do it for Linux, which is even easier than Windows). Which leads me to my next question...

2. How well does Toga take advantage of 64 bit? Anyone run any tests? Toga uses bitboards if I remember right, and so the speedup should be notable, but the lack of a 64 bit Toga in tournaments/rating lists has me wondering.

3. I know the question has been asked before because I've seen it here, but since I'm not finding in the archives what I'm looking for, has anyone implemented SMP support to Toga, and how successful was it? I remember someone saying it's been tried before(though I've yet to see it), and I know Tord said his SMP code was almost just a matter of copy/paste, but I'm wondering if anyone was working on it.

4. What are the well known deficiencies/bugs of Toga? I'm also looking for answers related to play style too. Does the search rely on more knowledge pruning(is that what you call it?) or brute force?

I have a few C++ college classes under my belt, but I want to work on something so that I don't lose what I know. I figure studying this code and trying to improve on it would be a way to go. Any information/help is appreciated.

Thanks.

[Michael Sherwin]

Toga a bitboard engine? That's news to me.

[revengeska]

I thought it was, but I could be wrong, I haven't actually looked at it.

[Dirt]

64 bit compiles for Toga are produced now and then. In every case I've seen they turn out to be slower that the 32 bit version.

Toga is not bit board.

[Uri Blass]

I thought it was, but I could be wrong, I haven't actually looked at it.

You are clearly wrong about it.

It is known that toga use no bitboards and you cannot get speed improvement from using 64 bits for it.

Uri

[revengeska]

I thought it was, but I could be wrong, I haven't actually looked at it.

You are clearly wrong about it.

It is known that toga use no bitboards and you cannot get speed improvement from using 64 bits for it.

Uri

Thanks for the clarification, Uri. I guess that's probably something that's holding the program back, I would think. Bitboards seem to be the best implementation for programs these days.

[Bryan Hofmann]

A few questions about Toga:

2. How well does Toga take advantage of 64 bit? Anyone run any tests? Toga uses bitboards if I remember right, and so the speedup should be notable, but the lack of a 64 bit Toga in tournaments/rating lists has me wondering.


Thanks.

Compiling Toga for 64 bit is certainly possible and I have done so many times for Windows and placed them on my site. The problem is that after countless hours of fiddling with the code and compile options you see less then a 5% speed up. This speed up means nothing in terms in increased strength.

Bryan

[revengeska]

A few questions about Toga:

2. How well does Toga take advantage of 64 bit? Anyone run any tests? Toga uses bitboards if I remember right, and so the speedup should be notable, but the lack of a 64 bit Toga in tournaments/rating lists has me wondering.


Thanks.

Compiling Toga for 64 bit is certainly possible and I have done so many times for Windows and placed them on my site. The problem is that after countless hours of fiddling with the code and compile options you see less then a 5% speed up. This speed up means nothing in terms in increased strength.

Bryan

Yeah, I've compiled it myself for Linux in 64 bit, but I hadn't really done comparison testing. You think that to take advantage of 64 bit, you'd have to perhaps rewrite the whole board representation as bitboard? That seems like quite a daunting task, and I'm wondering whether it'd require a rewrite of the search function as well. I guess I'd have to decide whether it would be worth it or not, but it's certainly a strong program despite these shortcomings.

[bob]

A few questions about Toga:

2. How well does Toga take advantage of 64 bit? Anyone run any tests? Toga uses bitboards if I remember right, and so the speedup should be notable, but the lack of a 64 bit Toga in tournaments/rating lists has me wondering.


Thanks.

Compiling Toga for 64 bit is certainly possible and I have done so many times for Windows and placed them on my site. The problem is that after countless hours of fiddling with the code and compile options you see less then a 5% speed up. This speed up means nothing in terms in increased strength.

Bryan

Yeah, I've compiled it myself for Linux in 64 bit, but I hadn't really done comparison testing. You think that to take advantage of 64 bit, you'd have to perhaps rewrite the whole board representation as bitboard? That seems like quite a daunting task, and I'm wondering whether it'd require a rewrite of the search function as well. I guess I'd have to decide whether it would be worth it or not, but it's certainly a strong program despite these shortcomings.

Search is totally independent of how the board is represented. But it would be a rewrite of the move generation stuff, evaluation stuff, SEE stuff, anything that actually modifies the board in any way or uses it...

[ed]

A few questions about Toga:

2. How well does Toga take advantage of 64 bit? Anyone run any tests? Toga uses bitboards if I remember right, and so the speedup should be notable, but the lack of a 64 bit Toga in tournaments/rating lists has me wondering.


Thanks.

Compiling Toga for 64 bit is certainly possible and I have done so many times for Windows and placed them on my site. The problem is that after countless hours of fiddling with the code and compile options you see less then a 5% speed up. This speed up means nothing in terms in increased strength.

Bryan

That's pretty disappointing with all those extra registers. Did you try the Intel 64-bits compiler as well?

Ed