## OpenCL LuxRender 0.9 is not using GPU

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### Re: OpenCL LuxRender 0.9 is not using GPU

Here are the Files, Scene file, Blend file and the geometry files, compressed of course.
3D.7z

Also here is a the scene rendered to 500 samples... took 20mins and saw the GPU do none of the work.

Please I need help with this... I have a 250 frame animation to render and I really want to use LuxRender to render it.

Cheers
Andy
skoot

Posts: 7
Joined: Tue Feb 21, 2012 6:31 am

### Re: OpenCL LuxRender 0.9 is not using GPU

Bump
skoot

Posts: 7
Joined: Tue Feb 21, 2012 6:31 am

### Re: OpenCL LuxRender 0.9 is not using GPU

Try to reduce the Path integrator max. depth from 105 to something more reasonable as 16 and set the number of shadow rays to 1, doesn't make any sense to use 2 shadow rays with a spot light.

There isn't very much else you can do. By using a single spot light, you have cut the most effective way to increase GPU load (i.e. multiple shadow rays, all uniform light strategy, etc.).

Posts: 4798
Joined: Sat Apr 19, 2008 6:04 pm
Location: Italy

### Re: OpenCL LuxRender 0.9 is not using GPU

I just upgraded my GPU to ATI HD 7770 and am having the same problem.

The Command:
Code: Select all
aticonfig --adapter=0 --od-getclocks --od-gettemperature

produces:

Code: Select all
Adapter 0 - AMD Radeon HD 7700 Series                            Core (MHz)    Memory (MHz)           Current Clocks :    300           150             Current Peak :    1000           1125  Configurable Peak Range : [300-1500]     [150-1625]                 GPU load :    0%Adapter 0 - AMD Radeon HD 7700 Series            Sensor 0: Temperature - 34.00 C

I'm using Lux version 0.9 (dev) of Apr 7 2012 64 bit OpenCL on Ubuntu 11.10. If I render any scene in Cycles or LuxMark the GPU load is pegged to above 95%. I have tried ray buffer size 512,1024,2048,4096 ect...

I have tried multiple spotlights, point light, and made some complex objects as I heard simple scene isn't efficeient...

zukazuka

Posts: 381
Joined: Tue Dec 09, 2008 10:01 am
Location: 西安 China

### Re: OpenCL LuxRender 0.9 is not using GPU

Well if your scene was lit by something such as a HDRi, I presume the performance increase would be more significant. I'm testing a few setups now to validate this (or invalidate)
i5 3.6GHz | 2 * 7970 GHz Edition | 8GB RAM | Shinobi XL Case
zeealpal

Posts: 484
Joined: Thu Feb 18, 2010 3:28 am
Location: Victoria, Australia

### Re: OpenCL LuxRender 0.9 is not using GPU

It seems that this is a reoccuring question by many people just starting out with GPU.

Maybe soemebody could include a .blend file with a "optimal GPU" scene with the right number of lights and vertices, and stuff...

I think something is wrong with my setup because GPU load is 0%.... having HDRI may have more work for it, but you would think without it the GPU load would at least be 5% or something??
zukazuka

Posts: 381
Joined: Tue Dec 09, 2008 10:01 am
Location: 西安 China

### Re: OpenCL LuxRender 0.9 is not using GPU

zukazuka wrote:I'm using Lux version 0.9 (dev) of Apr 7 2012 64 bit OpenCL on Ubuntu 11.10. If I render any scene in Cycles or LuxMark the GPU load is pegged to above 95%. I have tried ray buffer size 512,1024,2048,4096 ect...

I have tried multiple spotlights, point light, and made some complex objects as I heard simple scene isn't efficeient...

It can be very important to switch from "ONE" light strategy to "ALL" light strategy if you have multiple light sources and/or multiple shadow rays (i.e. you are using "ONE" light strategy).

Try to switch light strategy to "ALL" and to increase the number of shadow rays (i.e. 2, 4, 8, etc.) and try again to compare hybrid Vs. normal rendering performance.

P.S. LuxMark, SLG, Cycles are 100% GPU renderers, they don't suffer of the problem of balancing the load between CPU and GPU like hybrid rendering does.

Posts: 4798
Joined: Sat Apr 19, 2008 6:04 pm
Location: Italy

### Re: OpenCL LuxRender 0.9 is not using GPU

Dade wrote:It can be very important to switch from "ONE" light strategy to "ALL" light strategy if you have multiple light sources and/or multiple shadow rays (i.e. you are using "ONE" light strategy).

Try to switch light strategy to "ALL" and to increase the number of shadow rays (i.e. 2, 4, 8, etc.) and try again to compare hybrid Vs. normal rendering performance.

I was able to get GPU usage up to a continious 29% with shadow rays 1 and 39% with shadow rays 8 when I switch light strategy to "ALL"

For Hybrid Bidirectional I get:

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[Lux 2012-Apr-20 11:54:09] Incompatible lightstrategy for Hybrid Bidir (use "one").[Lux 2012-Apr-20 11:54:09] ERROR: Export aborted: Incompatible render settings
zukazuka

Posts: 381
Joined: Tue Dec 09, 2008 10:01 am
Location: 西安 China

### Re: OpenCL LuxRender 0.9 is not using GPU

zukazuka wrote:I was able to get GPU usage up to a continious 29% with shadow rays 1 and 39% with shadow rays 8 when I switch light strategy to "ALL"

For Hybrid Bidirectional I get:

Code: Select all
[Lux 2012-Apr-20 11:54:09] Incompatible lightstrategy for Hybrid Bidir (use "one").[Lux 2012-Apr-20 11:54:09] ERROR: Export aborted: Incompatible render settings

That is correct, hybrid bidir doesn't yet support "ALL" light strategy. However hybrid bidir is quite different from hybrid path tracing and it has less troubles generating a lot of rays to send to the GPU (i.e. higher GPU load). If you have troubles with memory usage just be sure to check the max. depth for eye and light path used in hybrid bidir: cutting in half the max. depth value can cut in half the amount of memory used.