Here we go again - falling back on cpu rendering, yet again
mumia76
Posts: 146
The age old problem is back again with 4.14. If I switch assets in the scene it will fall back to cpu rendering. I assume it fails to remove the instances of inactive assets from gpu memory therefore after a while it falls back on cpu because it runs of out of memory.
Closing daz studio, then reopening the exact same scene it again renders normally on gpu, for a while.
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I was wrong. I don'T even have to load new assets, it already happens when I turn off assets in the scene. Even with the iray preview. I load the scene it renders on gpu, I hide one item, it falls back on cpu instantly.
I'm getting a card with more memory when the stock is up. Probably January orr February, Scene Optimizer until then.
Are you using Section Planes? How much memory does your GPU have, and what is in the scene? Do you avoid this if the Viewport is in a non-GPU mode (not Filament or iray) when you start the render? Are you closing earlier render windows before starting a new render?
It was doing it even with the preview renderer. (I use iray preview to edit scenes most of the time, to see results real time) I'd load the scene it'd render on the gpu, but when I changed anything in the scene like hiding an object or changing the view, it would fall back on cpu rendering. If then and there I'd save the scene, quit daz studio, then start it again, load the same scene, it'd render on gpu again....until I changed something.
But that was yesterday, today I'm not able to reproduce the same issue. It renders the same scene normally now. Very temperamental.
Yeah, this was the same with 4.12 in the beginning. I have it too with 4.14 now. Have to close completely, like as in waiting till task manager ended the session, and restart.
It seems something is regressing here. 4.12 had it in the beginning too, until something was changed I guess. It would be nice if some options would be availabe to manage this!
This is the instance management feature - you either need the default instance to fully close or you need to use a different name for the second instance you start.
Instances? Daz Studio Pro 4.12 - instances
Thank you Richard, that seems interesting.
Also I found out if I kill "nv_container" task , that the memory seem to refresh and I can render again. But this is hardly a good work around :P
Another point I saw in the benchmark thread is that 4.14 adds another 500MB use to VRAM, which is great for speed, but not so good if you're already pushing the memory to its limits. Thinking of instances : It would be great if you could render with older Iray profiles, if such a thing is possible... So you could choose the more mem hungry latest Iray, or the the older version which are more lenient.
Not using section planes. 11GB VRAM, it would be so great if the iray renderer would actually display the VRAM required to render the scene on GPU, and an exact reason for the CPU fallback when that happens. And the fallback shouldn't be automatic! When for some reason GPU rendering fails, it should give a message: " Hey stoooopid, gpu render failed for this and this exact reason, do you want to continue rendering on CPU or cancel?" I didn't buy a $1000 GPU to then be stuck rendering on my CPU 100 times slower.
CPU fallback (without prompting) is the default behaviour - set in the Advanced tab of Render Settings (a restart is needed after changing it).
Unfortunately there isn't a way to pre-claculate how much memory will be used, and for error messages DS is limited to what Iray provides (which get written to the log).
Considering that issue, could you add more information about memory usage to the Iray render log window?
It already tells texture, geometry, etc memory usage but we need "total memory used" and "free GPU memory" and something to keep those numbers permanently visible as they quickly scroll away and are hard to catch.
I believe it would be very useful if we could see memory consumption without opening the log file every time and also it would be easier to understand when the scene is getting close to running out of memory.
also to troubleshoot those problems it would be even easier and better to report GPU memory on each line saying "Iray (Iteration) : "
Just 2 numbers of how much memory is used and how much is free. since it seems that sometimes memory usage changes during rendering.
I don't know if that information is supplied by Iray, or whether it could be calculated. You could certainly make a feature request for some kind of display of the base usage properties that can be scraped from the progress messages by opening a Tech Support ticket https://www.daz3d.com/help
my cpu render times and gpu render times weren't that different (older cars and a dual xeon machine .. which may mean my gpu renders are slower but cpu renders are faster than average) but there are small programs that will throttle daz when it tries to run away.. I have in locked at 66% and can pretty much do anything I want if it does fall over and there are a couple small programs that will show you what the card is using... I can have in open on another monitor and then watch we it does once the render starts.
But I do keep the renders on the gpu as much as possible.. the cpus renders are noisy....