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[bluewanderer]

Is it possible to write to global memory bypassing the cache like we can do on CPU?

It seems that in most situations we don't write temporal values to global memory. Actually I never met any case that caching writes is useful.

[dipak]

Sorry for this late reply.

No, you can't do in OpenCL right now. However, we are considering this feature for a future release. The Khronos OpenCL working group is also aware of a request for this.

Regards,

[boxerab]

Any updates on opencl non-temporal stores ? By the way, recent Ryzen perf improvements involved

removing unnecessary NT stores.

[dipak]

Sorry, there is no update at this point. I'll share if I get to know any.

Regards,

[tzachi_621]

You can do that with AMD GPUs if you have the time to patch GPU ISA.

See GCN instruction set arch​ , load/store instructions have a bit called 'SLC', - System Level Coherent, if it is flipped the GPU basically bypasses all its caches.

Tzachi