Weird Vram behaviour

[Mikla]

Hi there;

While I was testing the new 2020 2 Preview Release I ran into some Vram issues. The scene was working without any problems on 2020 1.5 but throwing insufficient vram errors on 2020 2.

I dediced to optimize my scene and keep an eye on the used vram. After some instancing i got the scene from 7gb down to 4.5gb. This of course significantly improved my render time on 2020 1.5

Then I decided to give 2020-2 another go and started to render again. To my surprise the scene went back to 7gb again.

Wanted to cross check the results so I went back to 2020-1.5 again. When I started rendering the scene went back to 7gb!

Utterly confused I started to render the scene on Live Viewer instead. The used vram went down to 4.5gb. Then when I render the scene in picture viewer it showed the same 4.5gb vram usage.

So it appears that when I render the scene in Live Viewer first the used vram drops significantly. If I render the scene to picture viewer from the start the vram usage skyrockets.

I also noticed that this isn't a case of octane showing wrong vram stats as my render time dropped from 1min25sec to 1min as well.

Is this a known issue? I can get around this thing just by rendering the scene in live viewer first of course but that isn't ideal. Also this wouldn't work with render queues.

Best.

Edit: I have just tried the same trick on 2020-2 and the results are the same. 7gb from directly rendering to picture viewer, 4.5gb if I render in LV first then in PV.

[bepeg4d]

Sorry Mikla, I cannot reproduce the issue here with my scenes.
Please, save the project with assets, compress the resulting folder, and share it via dropbox or google drive, or any other similar service, with me via Private Message, thanks.

ciao Beppe

[aoktar]

Be sure you don't have another app with using VRAM sametime. AE/pshop/etc.. can consume much. Also record a video to show your issue and post it pls

[Mikla]

will record video whenever possible. Thanks!

Edit: Sent the capture to Ahmet.