RT working in CPU not GPU

[vlado]

One thing I noticed in the log is an undocumented environment variable that Vray says it can't find called VRAY_OPENCL_PLATFORMS_x64. Can someone shed some light on this? Perhaps setting it would help.

It doesn't matter that the variable is not defined. It is set by the ocldeviceselect utility and is useful if you have more than one GPU installed.

Also, I looked at the environment variables Vray setup on installation (I used the .exe, not the zip file) and under System Variables there is one called VRAY_PATH with no value associated. What should the path be? Is this by design? Not sure if the installer messed up.

V-Ray does not use this variable (it was added by the previous installers for information purposes).

Which is the driver version by the way (as reported by the NVidia Control panel, should be something like 276.xx or similar, not the cryptic 8.17.12.7642)?

In any case, do you get any processor usage while the OpenCL program is being built? If yes, then it is not hung, just taking its (very long) time. On the not-so-bright side, GeForce cards tend to work much better for this.

Best regards,
Vlado

[nbreslow]

It doesn't matter that the variable is not defined. It is set by the ocldeviceselect utility and is useful if you have more than one GPU installed.

Isn't the 'ocldeviceselect utility' a 3DSMax tool? I am using Vray for Maya. Setting it couldn't hurt right? One less error. Would I set it to the device number? (i.e. 0 for my one GPU)

V-Ray does not use this variable (it was added by the previous installers for information purposes).

Noted - will delete that entry.

Which is the driver version by the way (as reported by the NVidia Control panel, should be something like 276.xx or similar, not the cryptic 8.17.12.7642)?

Sorry about that - it is the Quadro 276.42 driver. I have had no issues with it at all and it has been available on the Nvidia site for about 6 weeks.

In any case, do you get any processor usage while the OpenCL program is being built? If yes, then it is not hung, just taking its (very long) time.

According to the Windows Task Manager\Processes\vray.exe holds at a steady 4% in the CPU column while trying to build.

I looked in the Maya Script Editor and saw this:

// Warning: [SettingsJPEG] No image writer specified. // 
// Warning: [SettingsPNG] No image writer specified. // 
// Warning: [SettingsEXR] No image writer specified. // 
// Warning: [SettingsTGA] No image writer specified. // 
// Warning: [SettingsTIFF] No image writer specified. // 
// Warning: [SettingsSGI] No image writer specified. // 
// Warning: No scene found; cannot create OpenCL renderer plugin. // 
// Warning: Scene is empty. //

What is this 'Scene not found' issue? It seems to me that I could let this try to build forever but if it can't find a scene, whats the use?

Also, when I close the Vray command window while it is trying to build the Maya Script Editor returns: // Warning: Render host bresboxx (127.0.0.1) is not responding //

Could this be some sort of communication error? Just trying to think of everything.

On the not-so-bright side, GeForce cards tend to work much better for this.

That isn't what I want to hear... And frankly, at this point, shouldn't be the case.

Thanks,

-Nick Breslow

[vlado]

Isn't the 'ocldeviceselect utility' a 3DSMax tool? I am using Vray for Maya. Setting it couldn't hurt right? One less error. Would I set it to the device number? (i.e. 0 for my one GPU)

No, it's not just a number unfortunately; it would be best to leave this alone - things will work fine (assuming they work out eventually )

Sorry about that - it is the Quadro 276.42 driver. I have had no issues with it at all and it has been available on the Nvidia site for about 6 weeks.

Ok then; there is a developer driver for CUDA 4.1 that might work better, but I don't know if it supports Tesla/Quadro cards, but I'm not sure it will work, I have to try it out.

According to the Windows Task Manager\Processes\vray.exe holds at a steady 4% in the CPU column while trying to build.

Ok then; here it takes about 1 hour 10 minutes of that to build the code for a Tesla 2075 card.

What is this 'Scene not found' issue? It seems to me that I could let this try to build forever but if it can't find a scene, whats the use?

For this particular issue, it doesn't matter what it says in Maya; the OpenCL runs in the V-Ray Standalone, not in the V-Ray for Maya plugin.

Could this be some sort of communication error?

Nope. It's just slow. Waiting it out is the only way to get it working.

Best regards,
Vlado

[nbreslow]

Hi Vlado,

First, thanks for the quick and informative replies - very much appreciated.

Ok then; here it takes about 1 hour 10 minutes of that to build the code for a Tesla 2075 card.

Jeez - I literally let it run for 2 hours last night and no luck. Does it confirm the build in the Vray command window when complete? I seem to remember it confirming the build and giving the time. It used to just 'work'. I guess I am just a bit dumbfounded as to why my machine with the specs listed above (it rips through everything else) could be taking so long.

The compiled binary winds up somewhere, right? I think a Win user temp folder if memory serves. Can I watch there to confirm it is actually building? If so, what folder? And if I do get this going, how can I make sure it doesn't get deleted - seems like the Temp folder isn't the best place for this.

Thanks,

-Nick Breslow

[vlado]

Does it confirm the build in the Vray command window when complete? I seem to remember it confirming the build and giving the time.

Yes, it will be obvious when it is done.

It used to just 'work'.

Our OpenCL code gets more complicated, so I guess the OpenCL compiler needs more time (why it needs it only on Quadro/Tesla cards though is beyond me).

I guess I am just a bit dumbfounded as to why my machine with the specs listed above (it rips through everything else) could be taking so long.

I'd love to know that too, but only the guys at nVidia know the answer

The compiled binary winds up somewhere, right? I think a Win user temp folder if memory serves. Can I watch there to confirm it is actually building? If so, what folder? And if I do get this going, how can I make sure it doesn't get deleted - seems like the Temp folder isn't the best place for this.

It is in the temp folder and in fact I just realised that we do have a Quadro 5000 card here and I can just give you the compiled code to dump into your temp folder - I will try to do that tomorrow.

Best regards,
Vlado

[nbreslow]

Vlado,

It is in the temp folder and in fact I just realized that we do have a Quadro 5000 card here and I can just give you the compiled code to dump into your temp folder - I will try to do that tomorrow.

You are a real gentleman and all around great guy - Thanks so much. I will give it another shot also..do you know the path (i.e. is it in a sub-folder or just %USERPROFILE%\AppData\Local\Temp) it ultimately winds up in?

-Nick Breslow

[vlado]

Just type %temp% in Windows explorer and you'll get there.

Best regards,
Vlado

[nbreslow]

Got it - will look for your Quadro compile tomorrow and attempt my own. Thanks again,

-Nick Breslow

[nbreslow]

Vlado!

It finally worked - took 3 hours 20 minutes. I guess I wasn't patient enough. Thanks for all your help - I guess persistence pays off. Very much appreciated,

-Nick Breslow

[tobihofer]

If it crashes on CPU, then it's a different issue. Does it happen on any scene?

Best regards,
Vlado

Yes, happens on any scene.

Best regards, Tobi

[vaslavo]

sorry, im having the same problem with radeon hd 7970 on mac pro, cpu renders fine, gpu blue screen, did anyone try this card yet? sorry my native language is spanish.

[vlado]

I just got a 7970 a few days ago, but I haven't plugged it into my workstation yet; I hope to get there tomorrow and see how it goes.

Best regards,
Vlado