Statistic or Tracking percent working of CPU/GPU in GPU bucket rendering.

[duykhang]

Hi,
When rendering a scene with GPU next, bucket and hybrid mode ( CPU + GPU) i found this in V-ray messages " Using 38 threads for CPU, 6 threads per GPU device".
I have some question about this :
1. My CPU is Dual Xeon E5-2680v2, the total is 20 cores-40 threads, why rendering use 38 threads only? ( my GPU in this case is 1060 6GB)
2. I check in task manager: there are full load 40 threads?
3. When rendering is done, may i track or statistic how many percent in Image that's rendered by CPU/GPU? Just my personal research to compare efficiency between CPU and GPU.
Thank you

[savage309]

1. So it is using 44 threads in total (38 + 6), not 40. This is the case as 6 threads will be used to feed the GPUs. These threads will often wait for the GPUs to complete their tasks and provide them new ones. 38 threads are used for the CPU raytracing, as some resources were dedicated for managing the GPUs.
2. Yep (should be more clear why based on my answer on 1).
3. Not really, best you can get is render with GPUs once, and than render with CPU+GPUs and compare the render time.

Best,
Blago.

[duykhang]

1. So it is using 44 threads in total (38 + 6), not 40. This is the case as 6 threads will be used to feed the GPUs. These threads will often wait for the GPUs to complete their tasks and provide them new ones. 38 threads are used for the CPU raytracing, as some resources were dedicated for managing the GPUs.

Best,
Blago.

But my CPU total only have 40 threads, where is 04 plus threads come from? May I have miss understand that V-ray use threads are the difference with logical threads from my CPUs - Dual Xeon E5-2608V2?
thank you

[vlado]

The logic is more complicated as the CPU has to both render and feed data to the GPU, so the total number of active threads may be greater than the number of CPU cores you have in the system.

Currently we don't have a statistic to say how much of the image was rendered by each hardware device, but I will put it on the wish list.

Best regards,
Vlado

[duykhang]

The logic is more complicated as the CPU has to both render and feed data to the GPU, so the total number of active threads may be greater than the number of CPU cores you have in the system.

Currently we don't have a statistic to say how much of the image was rendered by each hardware device, but I will put it on the wish list.

Best regards,
Vlado

Thank you, everything is clear for me.
I hope this feature will be added someday.