Kernel not launched without errors


I have a problem with CUDA in ‘real’ mode. My compile and run well in emulation mode but the kernel is not launched in ‘normal’ mode. I don’t understand and there is no error reported by the following code. I also checked cudaMemcpy and cudaMalloc for a,b,c,d and e variables, but there is no errors. There is also no errors at compilation time (both emulation and normal mode)

process <<< dimGrid, dimBlock >>> (a, b, c, d, e);

printf("ERR:  %s \n", cudaGetErrorString( cudaGetLastError() ));


printf("ERR:  %s \n", cudaGetErrorString( cudaGetLastError() ));

cudaMemcpy(x, d, len, cudaMemcpyDeviceToHost);

printf("ERR:  %s \n", cudaGetErrorString( cudaGetLastError() ));

I’m compiling the code with the following command line (I’m under Linux =))

// emu

nvcc -o test -L /opt/cuda/lib/ -lcuda -lcudart -O3 -I /opt/cuda/include --device-emulation


// normal

nvcc -o test -L /opt/cuda/lib/ -lcuda -lcudart -O3 -I /opt/cuda/include

What kind of tools/functions/variables/debugger(/anything!) can I use to troubleshoot my app ?

Do you also know what kind of errors can make a kenel do not launch ?

I don’t know if this is useful but my card is a GTX260.


What do you mean when you say the kernel is not launched?

Hello Mr_Nuke,

I’m sorry for the delay. I finally found the problem : me ! :) (in IT field, the problem is always between the chair and the computer)

Seriously there were a bug in my code. I don’t remind it, but it’s solved.

Thanks for your help.

That’s why I like to sit behing the chair.