Loading kernels when using OPTIX

I just bought RTX 3070ti and was testing it and noticed that when using OPTIX it takes ages to load kernels the first time. For example, splash screen from blender 2.78 “blenderman” takes 6min to load when using OPTIX, is this normal behavior?

Loading kernels takes ages when using OPTIX first time

6 mins seems excessive but I don’t know the technicalities of kernels or how demanding that render is.

All I can tell you is, for me, using a 5700xt Red Devil gpu, a simple scene usually takes a min or 2 to load kernels for first time when opening blender.

I have been having the same issue now and then. I think I noticed it the first time in Blender 2.92.
It is not necessarily only the first time. It pops up now and then in scenes which I have allready rendered with optix before.

It is also possible that an Optix Cache file is bad. In that case you have to delete it by hand.
On Windows it can be found in
Just delete the files there or rename them and the next time you render optix will create a new one.

I have a 2070 super and a 2080 super, so it is not only the 30xx series.

Thanks for the reply! :slight_smile: I tried your suggestion and the issue is still there.
When Optix loads it’s amazing how good it is but this kernel loading inconsistency is just so frustrating. :frowning:

I am not 100% sure but I think I run into this problem when my c: drive is pretty full.

Which usually happens when I download a new Blender version and forget to change Blenders temp file directory to somewhere else than the c: drive.

Same here with my RTX 3060.

my 3060ti doesnt even load up the scene . it jus sits there loading kernels.

Used to happen few times but now it happens all the time and cannot render or use the viewport

It’s happened to me a couple of times on my old 970. It’s taken upwards of 10 minutes for it to load before, but once it does, it fires up smoothly thereafter.

All I can say is wait for about, say, 15 minutes. If it doesn’t load by then, then it might be time to switch to something else.

OK so after loading default cube for like 10 mins it finally worked. And now suddenly optix works with everything !