PGI User Forum

[xray]

Hi,
on Fermi GPUs, the default global memory access pattern are caching loads (i.e. a granularity of 128-bytes). With CUDA, you may change it to non-caching loads by compiling with nvcc and "-Xptxas -dlcm=cg".
With PGI's OpenACC, I assume we also have caching loads be default. Right? Is there any chance to use non-caching loads with OpenACC (compiler flag, environment variable,...)?
Sandra

[mkcolg]

Hi Sandra,

We do have an experimental flag (-Mx,180,8) that will disable the L1 cache. You are welcome to give it a try. The caveat being that since it's not been exposed at the user level, it is subject to change.

- Mat

[xray]

Thanks Mat! I will give it a try and will report my results.