Ok, what happens here is classic performance loss by paging.
What happens, is that Windows creates a so called "pagefile", which off loads the memory from RAM to the Harddrive, one's it's full. It starts with Idle background processes and then goes to whatever it can offload.
Your Harddrive has only a fraction of the speed, especially in random read and writes, of RAM. Thus the CPU starves for data to crunch.
tl;dr: you are out of RAM
I presume your many Distributed systems as well.
You have commited 57gb and only avalible are 32gb, meaning you have to clear 25gb of Scene data to get the performance back to Optimal. (presuming all your render slaves have 32gb RAM aswell)
You can achieve this by making your foliage fade out by distance. I know some scatter programs have this, but you can even do this manually. Scatter only 50% foilage after 20 meters and only 10% after 50m.
Care with dispalcements! At such crazy crazy resolution the default 2px displacement subdivision calculation will produce a crap ton of geometry. This is the same as 1px displacement at half the resolution or 0.5px at quarter the resolution.
And as a last resort: Your Framebuffer will be massive, you can use Backburner's stripe render to let each machine only have a small framebuffer and combine the result at the end. This will make using the Framebuffers functions very difficult, but will distribute the RAM needed for the whole thing across multiple machines. So only as a last resort.
If you need a quick test: Disable foilage and diaplacements, now render should go fast. Or even white material override for even more free ram tests.
« Last Edit: 2016-07-28, 12:37:24 by SairesArt »

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