Proxys disappear while rendering on backburner

Hey,
I have a large scene with trees build with models out of speedtree which are placed as proxys.
If I now render a sequence of this scene with Backburner some rendernodes are not rendering the proxys for random images - they disappear from the scene without any (recognizable) error.

We have a mixed Windows (7 and 10) Environment with 3ds Max 2018.4 and V-Ray 3.60.04. All pathes are UNC and Backburner-Server is running as application under the current artist logged on the maschine (not as a service!) with full rights to access the content/fileshares.

Attached you find 2 V-Ray Log files of the same rendernode - one where the proxys were successfully rendered and one that did not render successfully..

Thanks in advanced for any hints, tipps and for condolences :slight_smile:

Cheers!
vray_frame_failed.txt (45.9 KB)
vray_frame_success.txt (45.9 KB)

We had a similar issue before which was fixed (Denoiser generating black geometry on VrayProxys with MotionBlur on - Issues - Chaos Forum). Do you use motion blur and denoiser in your scene? Could you please double check whether all the machines are using the same V-Ray version?

Yes, I use denoiser - but no motionblur is enabled. All machines have the same V-Ray version (3.60.04).

Sorry - that’s not true: the camera motion blur is ticked on (isn’t by default?!)

In this case it would be best if you could send us the scene to support@chaosgroup.com so we could test it and investigate further. Please make sure to mention this forum thread in your e-mail.
Also motion blur is disabled by default.

Are you using UNC paths. Had same issue with proxy’s once I reattached using UNC paths it corrected it’s self.

Hey,
I did a test with rendering the same sequence and “Camera Motion Blur” ticked off (“Motion Blur” also, but that’s the default) - with success! All proxys rendered correctly.

Is there still an interest at the scene? If so, I’ll upload it accordingly on our server…

Cheers!

Yes there is, please send it over. In V-Ray 3.60.04 this issue should be fixed already. We need to check why the problem still occurs with your scene.

Hmm.. now I’m not so sure that my problem this is the bug as you mentioned, Zdravko.

After the successfully test with all Motion Blur Parameters ticked off, I rendered some more sequences.. and again: some rendernodes dropped for some frames all proxies. Currently I render a Irradiance Map Cache (Multi-Increment) with some Clients with V-Ray Spawner and the problem is the same - some clients are not loading the proxies correctly (look at the screenshot attached). If I did not know better, I would say the proxies do not have UNC paths - but they do - I I checked it a hundred times :slight_smile:

Some ideas?
Cheers!

Happy new year! :slight_smile:
Any news on this issue?! Is it the same as you mentioned? Or is it a user-based error?

Looking at the screenshot - is it possible that you’re using BackBurner along with Distributed rendering, all nodes added in both as render servers? If that’s the case - Backburner and V-Ray Distributed Rendering work in different way regarding job distribution.
Unfortunately Backburner does not directly support V-Ray DR. This is because Backburner distributes jobs frame by frame - for example Node 1 receives frame 1, Node2 receives frame 2 etc.
Distributed Rendering (by design) distributes EVERY frame between all nodes. This is achieved by dividing the frame to pieces (called “Buckets”) that are distributed to the different nodes, rendered, and after that compiled into the ready image ( Chaos Docs ). For example - if you have 6 render nodes Node1 will receive 1/6 of the frame’s buckets, Node 2 will receive another 1/6 and so on. That way Frame 1 is rendered by all 6 render nodes, after that frame 2 is also rendered by all nodes etc.

As you can see - if you try to render by simultaniously using DR and Backburner with all nodes there will be a problem in rendering, because:

1. Every Render Slave receives a whole different frame to render from Backburner

but also

2. Every Render Slave receives Buckets (or pieces) from every frame one by one from Distributed Rendering’s algorithm , including the frames already received from Backburner

The result will be mismatch and problems in rendering.

A way to work around this will be to either:

1. Configure DR on your workstation the way you want and add ONLY the main workstation in Backburner. That way you can schedule jobs in Backburner, they will be submitted correctly to the workstation Frame by Frame and since your main workstation is the only node all frames will go there. The workstation will than redistribute the frames using DR.

2. Use only DR

3. Use only Backburner

Hey Ivan,
thanks for your detailed explanation - but I rendered the frame local and not on backburner.

However, yesterday I found out by chance that sometimes our DNS is causing problems not resolving the requests properly. Although I do not understand why this concerns only the proxys (especially since “Check for missing files” is checked!) and not the rest (like textures or gi-caches) - but that could be a logical explanation why some frames drops the proxys

I wrote that yesterday via email to the error report (070-729-323).