Low CPU utilization over Network Render

[monson67]

We recently replaced our two Network Rendering machines, both with an Intel Core i7-6900K 3.2GHz 8-Core (16-thread) CPU. We're now using a single computer with an AMD Ryzen Threadripper 3970X 3.7GHz 32-Core (64 -thread) CPU. I was surprised to find that the renders I was sending to the network were taking longer.

I checked the CPU performance from the task manager, and it's averaging 10-15% utilization at underclocked speeds with occasional, very brief jumps up to 50% utilization (first screenshot attached). To troubleshoot, I installed a trial version of KeyShot on the machine and rendered the same scene, and it cranked it out in no time. Real-time render was also blistering. In both real-time render and output render, the CPU performance was constantly showing 100% utilization with overclocked speeds (second screenshot attached).

Does anyone have any idea why this would happen?

[mattjgerard]

No answer but I agree that the NR is not as good as a local install at CPU usage. Not sure why, but I'd like to follow to see what the experts say.

[DriesV]

Hi monson67,

What kind of scenes are you sending to NR? Can you share an example where you see the degraded performance?

It would be nice to get some specifics on:

• render mode used (Product Mode/ Interior Mode)
• image resolution
• etc.

Dries

[monson67]

The scene doesn't seem to matter. So rather than explain all of the specific lighting, camera, material and geometry settings of a complicated scene, I figured I'd create a new, blank scene with default settings. That way, it should eliminate a ton of variables. I added a cube from the KeyShot "Add Geometry" menu, and left it with the default diffuse material. Sent that to NR, still only 10% from the CPU.

From there, I ran some other tests using the same simple scene. I turned on Performance Mode and sent that to NR. I tried some with different resolutions, from my standard 5120x3072 (5k at a 5:3 aspect ratio), down to 1000x1000. I changed the output file types, using png, jpg and tif. I also changed from product mode to interior mode. All with the same ~10% utilization.

I'm sure I'm missing other things to try. Let me know, and I'll run some more tests.

[SebastianG]

How many cores are set in the "Network slave tray"? (Right click on the symbol)
Try to change it to all cores.

How many cores can use with your Network rendering license? Maybe you have other machines in the network and more cores than licensed.

[monson67]

Is/was set to "All Cores".

We have a 64-core Network Render license, and the Network Render machine we just set up has a 32-core CPU (64 threads). I removed the old machines from the Network Render. Still scratching our heads.