I really appreciatte your opinion and THANKS A LOT!! I will check what I can do... Best Regards, Marcelo
--- Em qua, 6/5/09, Tobias Reneskog <[email protected]> escreveu: De: Tobias Reneskog <[email protected]> Assunto: Re: [foxboard] Access Memory Delay - !!!!HELP, PLEASE!!!! Para: [email protected] Data: Quarta-feira, 6 de Maio de 2009, 17:49 Hello! Well, the the code also does one million floating point operations (fSum++) in addition to filling that vector. If you assume that all the time is spent on the line "fSum++", you get that each iteration takes ~700 instructions. That looks quite reasonable to me, considering the floating point math is a pure software implementation. If you need better performance, you have to use a processor with an FPU. Regards /Tobias companymvms skrev: Dear All, I did the measurements performs of my program inside a FoxBoard LX832. I am really upset because the Fox is spend 7 seconds only to fill a vector with 1000 positions. Look the part of the code,(it's simplified to highlight the problem), that spend this time: float fSum = 0; float result; int plus = 0; for (int i=0;i<999;i+ +) { for (int j=0;j<928;j+ +) { fSum++; } m_pfConductivities[ i]=fSum; //I HAVE SURE THAT THE PROBLEM IS THIS LINE THAT TAKES SO MUCH TIME TO WRITE A VECTOR. plus += 928; } If I replace THE VECTOR m_pfConductivities by a float variable ex: float result; It will takes only 16ms to processed this operation. I really needs to storage the 999 results in any kind of array... I think the problem is the time to access the memory... Any suggestions? p.s.: I tried to use int instead of float, I tried to use <vector> stl definitions, I tried to use memset, I tried to use float static... I don't know how to solve... Help me please... --> Really thanks in advance.. Veja quais são os assuntos do momento no Yahoo! +Buscados http://br.maisbuscados.yahoo.com
