Can it occur that 2 kernels run at the same time if the 2 kernels are continuously launched?

Accelerated Computing CUDA CUDA Programming and Performance
1

Can it occur that 2 kernels run at the same time if the 2 kernels are continuously launched?

For instance, Device Spec is as follows for brevity.

num of SM       = 4
    CUDA Cores / SM = 1
    CUDA Cores      = 4

The code is as follows.

Kernel1 <<< 6 , 1 >>> ();
    Kernel2 <<< 6 , 1 >>> ();

Which of the following is actual behavior?

case A
                SM1         SM2         SM3         SM4
    -------------------------------------------------------
    time1       Kernel1     Kernel1     Kernel1     Kernel1
    time2       Kernel1     Kernel1
    time3       Kernel2     Kernel2     Kernel2     Kernel2
    time4       Kernel2     Kernel2

case B
                SM1         SM2         SM3         SM4
    -------------------------------------------------------
    time1       Kernel1     Kernel1     Kernel1     Kernel1
    time2       Kernel1     Kernel1     Kernel2     Kernel2        <- simultaneously
    time3       Kernel2     Kernel2     Kernel2     Kernel2
2

Two kernels, launched into the same stream, cannot run concurrently, at all, ever.

Your code is launching the kernels into the same stream. So something like your case A is what will happen.

[url]https://docs.nvidia.com/cuda/cuda-c-programming-guide/index.html#streams[/url]

3

Thank you for the reply.