High CPU Usage When Rendering With VRayRT GPU

[DanielBrew]

I'm just starting to use VRay RT so I don't know whether this is normal or not but I'm seeing CPU usage of 20 - 40% over all 8 CPU cores. The main culprit seems to be vray.exe.

I'm getting some ok results and can see the potential despite not having a very powerful GPU (Quadro 4000 2Gb). But main problem I'm having is the foreground performance of Max takes quite a hit when I launch the VRay RT. It then gets progressively worse until after a few minutes it becomes completely unresponsive. Is this because I only have one video card? Or could it be caused by vray.exe hogging the CPU.

My system specs are:
Windows 7 Pro
2 x 4 core Xeon 5355
8Gb ram
Quadro 4000 2Gb - driver 295.73

Thanks,

Dan

[vlado]

I'm just starting to use VRay RT so I don't know whether this is normal or not but I'm seeing CPU usage of 20 - 40% over all 8 CPU cores. The main culprit seems to be vray.exe.

This is normal; the CPU needs to do a bit of work to prepare the data for the GPU and to read the results back.

Is this because I only have one video card?

Yes.

Or could it be caused by vray.exe hogging the CPU.

No.

See this page for some tips about this problem: http://www.spot3d.com/vray/help/rt10...m#load_balance

Best regards,
Vlado

[DanielBrew]

Hi Vlado,

Thanks for your reply and thanks for the link, I'd missed that.

It's good to know everything is working as it should. As I said in my original post, I'm new to VRay RT so I'm experimenting a bit to determine whether VRay RT can do a job for us. If it can I need understand what hardware would we need to optimize its potential. I must say I'm getting some very impressive results on small scenes but the larger scenes are causing too much of a slowdown at present. Do larger scenes cause more work for the CPU because it has more data to prepare for the GPU?

Dan