LuxCoreRender Forums

Posted: **Tue Apr 21, 2020 7:25 am**

OMG... I have no words... I’m gonna cry... thanks...

Posted: **Tue Apr 21, 2020 7:57 am**

It is awesome))

Posted: **Tue Apr 21, 2020 8:13 am**

I gave it a try and...

On my system OpenCL runs about 9% faster than Cuda.

Posted: **Tue Apr 21, 2020 9:34 am**

acasta69 wrote: ↑Tue Apr 21, 2020 8:13 am I gave it a try and...
On my system OpenCL runs about 9% faster than Cuda.

I don't know if this is a bad or a good thing

But I'm expecting some proper perf. improvements once Dade starts adding cuda specific stuff.

Posted: **Tue Apr 21, 2020 9:42 am**

acasta69 wrote: ↑Tue Apr 21, 2020 8:13 am I gave it a try and...
On my system OpenCL runs about 9% faster than Cuda.

maybe this will vary from card to card also that run on 2070 super and you probably on GTX 970. but as Dade say he assume there is more performance left.

Posted: **Tue Apr 21, 2020 11:03 am**

acasta69 wrote: ↑Tue Apr 21, 2020 8:13 am I gave it a try and...
On my system OpenCL runs about 9% faster than Cuda.

I'm fixing a lot of stuff and CUDA has a lot of settings and configurations for each generation of GPU. Said that, I have now done more tests and the speedup is quite consistent with my RTX.

P.S. are you selecting only the CUDA device, right ? NVIDIA GPUs are now listed 2 times, one as OpenCL device and one as CUDA. I'm also doing the test with 0 CPU threads.

Posted: **Tue Apr 21, 2020 11:51 am**

Dade wrote: ↑Tue Apr 21, 2020 11:03 am P.S. are you selecting only the CUDA device, right ? NVIDIA GPUs are now listed 2 times, one as OpenCL device and one as CUDA. I'm also doing the test with 0 CPU threads.

Yes, I tried selecting different devices with e.g.

Code: Select all

opencl.devices.select = 001

The speed is smaller when CUDAIntersect is used and higher with OpenCLIntersect. The 8% speed difference is calculated only with GPU rays/second, though.
Also, how can I get rid of native threads? The following does not have any effect :

Code: Select all

native.threads.count = 0

Posted: **Tue Apr 21, 2020 12:40 pm**

acasta69 wrote: ↑Tue Apr 21, 2020 11:51 am The speed is smaller when CUDAIntersect is used and higher with OpenCLIntersect. The 8% speed difference is calculated only with GPU rays/second, though.

The result shouldn't change but the performance is usally measured with the samples/sec counter.

acasta69 wrote: ↑Tue Apr 21, 2020 11:51 am Also, how can I get rid of native threads? The following does not have any effect :
Code: Select all
native.threads.count = 0

With this:

Code: Select all

opencl.native.threads.count = 0

Posted: **Tue Apr 21, 2020 5:36 pm**

Dade wrote: ↑Tue Apr 21, 2020 12:40 pm The result shouldn't change but the performance is usally measured with the samples/sec counter.

Yes, I used the other value to exclude the native threads that I could not switch off.
Now, without native threads and samples/sec as reference, I have 12% faster performance with OpenCL.

I assume it is ok to use the Cuda-enabled executable and select either the Cuda or the OpenCL device, right?

Posted: **Tue Apr 21, 2020 6:21 pm**

acasta69 wrote: ↑Tue Apr 21, 2020 5:36 pm I assume it is ok to use the Cuda-enabled executable and select either the Cuda or the OpenCL device, right?

Yes, the default PATHOCL behavior now is to use only CUDA devices if at least one is available, this will work fine on NVIDIA-only installation where GPUs are exposed 2 times (and it will work fine with NVIDIA-without installation too where only OpenCL devices are used). Inded, aside the case where you explicitly select what devices to use.

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Re: PATHGPU with OpenCL and CUDA support

Re: PATHGPU with OpenCL and CUDA support

Re: PATHGPU with OpenCL and CUDA support

Re: PATHGPU with OpenCL and CUDA support

Re: PATHGPU with OpenCL and CUDA support

Re: PATHGPU with OpenCL and CUDA support