Running V-Ray RT on a CPU and GPU with OpenCL

[vlado]

Hi,

With the new 2.30 version of V-Ray RT, it is now possible to run the OpenCL code on CPU platforms as well without any hacks; here is a quick walk-through how to set it up.

1. Close 3ds Max and V-Ray RT render server if it is running;
2. Go to http://developer.amd.com/sdks/AMDAPP...s/default.aspx and download "AMD-APP-SDK-v2.6-Windows-64.exe"; the AMD software OpenCL implementation will work even if you have an Intel CPU and/or an nVidia GPU;
3. Run the installation, and choose Custom installation type. Only install the "AMD APP SDK Runtime". You do not need the developer SDK, the profiler, KernelAnalyzer or samples.
4. You may get a message that "warnings occurred during installation", but it seems to work fine anyways.
4. After the installation, go to Start menu > Programs > Chaos Group > V-Ray RT for 3ds Max > Select OpenCL devices for V-Ray RT
5. You should see a CPU device listed, something like "AMD Accelerated Parallel Processing..."
6. Enable that CPU device and click the "Set devices" button;
7. Start 3ds Max and select V-Ray RT with OpenCL engine.

Now the OpenCL engine will use both the CPU and the GPU to render. You'll have to test if this actually gives you any additional performance; in some cases if the GPU is very much faster than the CPU, the CPU rendering will only slow things down.

Best regards,
Vlado

[Bpositive]

So nice Vlado. Looking forward to test it

Will this work with networked rendering?

[vlado]

Will this work with networked rendering?

Yes, of course. You'll need to do the setup (installing the AMD APP runtime and then running ocldeviceselect) on the render servers as well.

Best regards,
Vlado

[Bpositive]

Sounds really good Then no computer will be allowed to rest for a moment

[Alan Iglesias]

Very interesting! Will set up and test today...

Thanks Vlado!

-Alan

[3LP]

Just to let you know,
I did what you said and I couldn't find the cpu in the opencl devices

I will try to reboot and give it a try afterwards

Is it supposed to be showed in the opencl devices directly after the installation ?

Thanks

Stan

[vlado]

Well, it shows up on my workstation and my laptop...

Best regards,
Vlado

[Kergnob]

my CPU and GPU properly show up in the OpenCL devices list, but when trying to run for OpenCL, it crashes (windows 7 informs me that V-Ray Standalone has stopped working) =(
Although there is a third option now CUDA (single kernal) that appears to work but dunno as to what exactly it does

AMD 5770, driver version 12.3

vray 2.30.01

3dsmax 2012 SP2

[vlado]

Try the CPU device only, it will probably work better (though not sure how useful that would be).

Best regards,
Vlado

[Kergnob]

using just CPU would be better than using GPU + CPU? On Vray 2.2 I was able to run GPU and CPU separately, but now the CPU / CUDA options are only available since the gpu+cpu option crashes. Will try reinstalling tonight to see if it helps. But what is the CUDA option if I am running an AMD card?

[vlado]

using just CPU would be better than using GPU + CPU?

To the extent that you won't be able to get the AMD GPU working, yes it will be better in the sense that at least it will work.

Best regards,
Vlado

[Kergnob]

haha then yes to the extent of either having VrayRT work or not work, yes the option of it working is the only option =P

On Vray 2.2 my amd gpu was working for VrayRT too so dunno what was done in the upgrade other then this addition but seemed to of hosed it, though it wasn't really viable for me in the first place since it locked up my machine while doing so (1 gfx card)

[Dariusz Makowski (Dadal)]

Vlado ure awesome thanks for update! =D

[Infrared digital]

I have just started using VRay RT and was wondering what the benefit of this is ?

[super gnu]

well instead of just using the GPU, it uses the cpu as well. id have thought the benefit would be obvious