[solved] Long computing secondary Gi calculation times

[PMVis]

Hi all,
I have been recently having an issue where I suddenly get really long calculation times for computing secondary gi since updating to corona 4. I actually had this issue some time ago when I switched from corona 2 to 3 but never really found a solution.

My scene was only needing seconds to calculate secondary gi but suddenly it's estimates an hour(i quit after 10 mins). If I restart my computer and render at a lower resolution it eventually works, but I have to restart my computer every time I change the camera and can't render at 3000 pixels or above.

I thought that this is a RAM issue but I'm not getting any RAM warnings. Also I tried it on a scene that was working before installing corona 4 and the scene just stops rendering after about 30 passes with cpu usage going down to like 5%.

I also tried checking the conserve memory box to no avail. Also I have a back up system(crashplan) running at the same time, could this interfere at all?

Has anybody else experienced this kind of issue? I would appreciate any help. Cheers!
Phil

[rowmanns]

Hi,

Please would you be able to provide your scene so we can investigate?

Instructions on how to do this are in my signiture, please don't forget to let me know the name of your file.

Thanks,

Rowan

[PMVis]

Hi.

Sure I can try and upload the scene but it's quite large and also this is happening across multiple scenes. I have actually had a support ticket(number #15678) on this same issue from about 6 months ago and there was no final solution to it back then. 

I have updated my graphic card drivers and that seems to help somewhat but the calculation times still jumped from 1min to 5min after just simply changing a chamfer amount on geometry.

Are there any ideas to try before uploading the scene?

[rowmanns]

Hi,

I'll speak to our support guys and find the ticket.

I will let you know once I've taken a look.

Thanks,

Rowan

[maru]

Previous ticket:
internal id=311368612
support ticket id=15678

@PMVis it would be great if you could send us this new scene, so that we would try reproducing the issue.

[maru]

Solved in ticket #28339 by:
- closing background programs
- setting 3ds Max priority to High