ekondis / gpumembench

A GPU benchmark suite for assessing on-chip GPU memory bandwidth
GNU General Public License v2.0
96 stars 23 forks source link

Memory bandwidth in terms of SM number #3

Open zhiqi-0 opened 3 years ago

zhiqi-0 commented 3 years ago

Hi, really thanks for the nice tool!

Just some quick questions, I'm not familiar with underlying designs of GPUs, and curious about the used memory bandwidth in terms of SM used number.

Can we only use one SM to saturate the memory bandwidth theoretically? Or will there be some contentions if multiple SMs are involved for accessing data in global memory, comparing only using one SM?

I'm not sure if it's correct to test the memory bandwidth achieved by, e.g., only one SM, by changing the following code to const int TOTAL_BLOCKS=1;.

https://github.com/ekondis/gpumembench/blob/838a4fcd5e6bdf8d09a10da10fb4b98bf484771a/cachebench-cuda/cache_kernels.cu#L353