64 bit performance speedup over 32 bit

[Lars Schouw]

Does anyone know how much performance speeup I can expect by using 64
bit C++ / Windows XP 64 bit over the 32 bit versions?

Did anyone test this under Visual Studio 2005 or Intel C++ 8.1/9.0 ?

My application domain is montecarlo simulations but any test would be
great.

Regards
Lars Schouw

 

[Bill Shortall]

Does anyone know how much performance speeup I can expect by using 64
bit C++ / Windows XP 64 bit over the 32 bit versions?

Did anyone test this under Visual Studio 2005 or Intel C++ 8.1/9.0 ?

My application domain is montecarlo simulations but any test would be
great.

Regards
Lars Schouw

Hi Lars,

I have done some comparisons while
developing a linear algebra package in C++ They are shown at
www.pecos-place.com/news
The comparisons were between a 32 bit
pentium 4 and a 64 bit athalon .Both used
windws XP - 32 bit The
Athalon was slightly faster maybe 10%
I also noticed that the execution times
for most matrix operations
were about the same for the three compilers I use VC6, VC7, Intel 8

regards....Bill

 

[Lars Schouw]

Bill

What happens if you run it under a Windows XP x64 and compile for 64
bit?

Thanks
Lars

 

[Bill Shortall]

Bill

What happens if you run it under a Windows XP x64 and compile for 64
bit?

Thanks
Lars

I don't have the 64 bit operating system yet, My guess is that you would
have to
be dealing with larger matrices say 5000x5000 before there was any
differance

Bill

 

[Ian Collins]

I don't have the 64 bit operating system yet, My guess is that you would
have to
be dealing with larger matrices say 5000x5000 before there was any
differance

You might be surprised, if the compiler is on the ball, the better
register set and call optimisation can make a big difference. It'd not
just 64 bit operations that benefit.

If you have an example, I can try some tests (not on windows).