Loading Bitmaps all the time

[supernoodles]

I have a PC with 2 x titan rtf cards with NV link. Nvidia drivers 441.28, V-Ray - 4.30 Build 00001.

When I move anything in a scene the VFB says loading bitmaps and it takes a around 6 seconds each time to refresh, before it begins to clean up. Is this correct? It seems cumbersome

[vlado]

I think it's doing something else and not actually loading bitmaps. It would be best to send a scene to support@chaosgroup.com so that we can see what's going on.

Best regards,
Vlado

[supernoodles]

I already have.

Thanks

[vlado]

Ok, thanks! Let's see what comes up.

Best regards,
Vlado

[supernoodles]

So I think I have found the problem. There are 2 substance materials in the scene that aren't baked to maps. Every time you try and move something, the VFB has to load new bitmaps. Presumably its generating new maps for the substance materials every time. GULP!

It still however, has to ' Build GPU dynamics nodes', & "Build Optix acceleration structures" for every move of a light or geometry. Is this correct?

[tashko.zashev]

Hi,

Edit :

Thanks for the update!
In my test everything worked fine here and I haven't modified anything. There are 5 Missing textures (2 pngs, 2 jpgs, 1 hdr) at scene open which might be critical for this.

[a7az0th]

supernoodles Hi

The 'Build GPU dynamics nodes' & 'Build Optix acceleration structures' part is fine, as long as long as it's fast. If you move a single piece of geometry/light in the scene we do have to rebuild acceleration structures only related to it, and that would be quite fast. If it isn't maybe there's a bug that we should look into.
As for the textures, unsupported textures are baked on the GPU and if a parameter for the texture is changed, then the textures need to be rebaked every time. Depending on the number of unsupported textures, this process can take a little while.

[tashko.zashev]

I'm still working on the scene and what have found so far is that there seems to be a problem with the building tree when Forest pack is present in the scene. Object or Camera transformations are slow here and we have to find what and where we need to make improvements.

[supernoodles]

I have also removed the forest pack elements and this seems to speed things up. Another issue which maybe related, is that after a period of having active shade running, the render appears to stop. If I try to restart the active shade, it goes through its process of getting ready and then says 'Compiling Kernels for device TITAN RTX' but then never restarts rendering. I have to quit Max and relaunch.

Could this be anything related?

[olika]

I recognized the same with this crashing kernel and then restart max to make it work. Did not had the time to investigate that much but seems to happen in different 3d scenes here. It's like supernoodles describes it. Happens after playing around a bit starting and stoping the rendering and then all of a sudden kernel is lost. Would be great you could have look at that. is my most bothering thing with gpu right now... thx in advance!

[a7az0th]

Could you send a V-Ray log over so we can check what's happening at the time of the issue. We haven't been able to reproduce such behaviour here.
Could you also share the driver version you are using?
It seems that OptiX has encountered a problem and the log should contain information what that problem is,

[supernoodles]

Here you go. I look forward to hearing what you find

Thanks
Nick

[supernoodles]

Any further feedback on this issue please?

[a7az0th]

We got the problem and indeed it is related to substance textures. During a bug in V-Ray each change during IPR forces a full reprocess of all substance textures.
We're working on a fix at the moment. The problem is logged in our internal bugtracker as VGPU-4433

[a7az0th]

So there was a bug and Substance textures were indeed reprocessed and reuploaded every time. The issue has been fixed and available soon.