Path Tracing - OC AMD A10-5800k 4.2ghz

Started by WAS, November 19, 2018, 02:57:17 pm

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November 19, 2018, 02:57:17 pm Last Edit: November 19, 2018, 11:23:21 pm by WASasquatch
When I path trace, render time is doubled. A 6hr render is still going at 12hrs.

But the concerning bit is TG is sucking upwards 120% usage, so much so my system is unstable and my PDANet application for broadband can't function (and AMD GPU suite crashed proceeding GPU driver crash)

I've noticed TG will use more CPU than it has access to with v3 clouds and I'll get 100%-105% usage but with path tracing its CPU utilization is out of control. I cant even take a screenshot with Lightshot and its such a light tool and hasnt crashed.

I cant even get a cmd prompt for linux-style CPU load readout for more details.

Edit: force closing explorer and wdm helps tremendously - 104-108% but still pretty unresponsive.


November 19, 2018, 03:25:31 pm #1 Last Edit: November 19, 2018, 03:28:33 pm by WASasquatch
My god. It would probably help if I did not ray trace the salt flats surface (not even sure why I re-enabled this). Way to much low scale displacement for not allocating time for something like this, and probably explains some of the rogue usage with clogged lanes computing all these rays.

It sure was looking good though (realized I can use windows print screen clipboard in irfanview). I'll try again tonight.


I wouldn't expect path tracing to actually make much difference on that image. And yes, it's going to take a good deal longer, it's more accurate and realistic and needs additional render time to make it so.

As for the >100% CPU usage, perhaps this explains:

But as I've said before, Terragen literally cannot use more CPU resources than Windows allows. If you have an issue with responsiveness I suggest you use the Preferences to reduce the number of threads allowed. By default it is based on the number Terragen detects on startup.

- Oshyan


November 19, 2018, 06:09:57 pm #3 Last Edit: November 19, 2018, 06:17:04 pm by WASasquatch
I wasn't aware Turbo Core in AMD even reported like that. It shows the the Maximum Frequency of the boosted cores, but usage (MU) is always just 100%, even when doing something like Folding@Home or CPU benchmark.

Terragen is the only program so far that will show overhead with v3 clouds and I guess path tracing.

This does seem to correspond to the Intel's Turbo Boost but I wonder why I don't see it with something like a straining cpu benchmark?


As for Path Tracing this scene, to my eyes, it gives a much better desert impression than standard renderer. The extra brightness in lighting and the shadows on the far-side of the mountain.


November 20, 2018, 05:20:45 am #4 Last Edit: November 20, 2018, 07:22:19 pm by WASasquatch
Additionally, why when a path traced render is paused, why does TG hold on to about 65-80% CPU and fluctuate around constantly?


When the render is paused, the 3D Preview (and other previews) may continue rendering. Maybe that's what happened?
Just because milk is white doesn't mean that clouds are made of milk.


Thanks, that makes sense.

I also encountered this last night trying to render a basic default scene with just clouds and some ground displacement. Wanted to see how shadows interacted being overcast.


Seems the path tracer doesn't support lots of shadow. This happens any time with overcast, v2 or v3.


Any word on what kills renders like this or how to prevent it? Have you encountered it?


Nope, haven't encountered it. And we haven't had any other reports of it either. If you want to provide us a TGD that it happens on, we're happy to see if we can replicate it. If it's something that is actually wrong with Terragen itself then it's likely we can. But it may be simply down to your constrained system resources.

Honestly I'd really recommend against using path tracing until you get more memory and/or a better computer in general. Unless something has already changed on your end that I'm not aware of, you're basically operating near minimum specs. And when we specify the minimum specs we don't expect people to then try really demanding renders, which path tracing would be considered.

- Oshyan


November 26, 2018, 07:01:25 pm #10 Last Edit: November 26, 2018, 07:23:19 pm by WASasquatch
Before I go stripping down a TGD , try doing any sort of complete cloud overcast scene letting through a far descent amount of light for the surface, and turn on path tracing and exaggerate surface details. Bout all I do as far as new features. Rest is just high quality GI (max scales) settings and AA.

I'll see if it happens in a small resolution document in the mean time.

Edit: oh yeah was also trying to to test the new Adaptive Curve