copy to __constant__ by cudaMemcpyToSymbol

Accelerated Computing CUDA CUDA Programming and Performance
1

Hi,

I defined a structure as
struct XXX
{
int a;
int b;
float4 vector_a;
float4 vector_b;
int c;
int d;

};

and declare an constant through constant

When I try to copy from host to device’s constant value through cudaMemcpyToSymbol,
but the struct’s vector_a(b) and scalar c/d seems are not copied to. Can anyone please
explain the reason? Thanks!

2

The cudaMemcpyToSymbol function takes a different number of args when compared to cudaMemcpy. See if you have given the args correctly – most importantly the “size”

3

Hi,

This is the memory alignment issue. float4 structure was declared as align(16).