AMD threadripper 1950x
X399 AORUS Gaming 7 motherboard
64 gb Ram
Running latest chipset drivers + up to date bios
Windows 10 64 bit running on gtx 970 GPU
**Blender Version 2.79
rendering large scene takes hours before render proces starts
To reproduce this problem, you need to load a large scene like the production demo scene from the blender benchmark. If you use the default performance settings it will take more time then rendering the scene with a low amount of threads.
the difference is huge. Default settings ( 32 threads) can slow down the rendering proces with 2 hours. Using 4 threads only takes minutes.
The more RAM a scene has, the more problematic this issue is. The difference in the production benchmark is 2 vs 7 minutes. The benchmark scene is +/- 10 GB Ram. If i render a scene with 30 GB ram it is 4 minutes vs 2 hours