Iray suddenly jacks CPU up to 100% (not the GPU→CPU crash)
Visuimag
Posts: 578
Okay, this one is weird. Since reinstalling Windows and DAZ a month and a half ago, I've encountered this issue. It generally happens after I've changed a setting in the Viewport (Texture Shaded) and then switch over to AUX Viewport (with Iray Preview on). My CPU will suddenly jump to 100% and the fan will continue to just crank up more and more (something that does not even happen with the usual GPU→CPU crash). This is new, and it forces me to kill DAZ with the Task Manager as it becomes unresponsive (this also doesn't happen with the GPU→CPU crash, where I can at least continue to use the program and my CPU fan doesn't become a jet engine). It didn't happen before I reinstalled Windows (or ever before, for that matter).
Instead of reinstalling again to see if I clear this issue, figured I'd turn to the community for help first, wondering if anyone else has ever experienced this. It is 'game-breaking' and only occurs when using Studio (version # doesn't matter, as it has happened in both 4.10 Pro and the 4.12 beta(s). Has happened when I know I haven't run out of GPU memory, either (in case someone suggests that being the case) and this has also happened on multiple NVIDIA drivers. Any help/ideas are greatly appreciated.
PC:
Titan Xp x 2
i9 7920X (12-core)
64GB RAM
1200W PSU
Rampage VI Apex
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Comments
The CPU pegging like indicates some sort of runaway process. If it only happens in DS then I'd check all your drivers, since no one else is reporting it. Make sure your GPU driver is up to date from Nvidia's site, make sure that Windows Update is not allowed to update drivers. If the graphics card is up to date then check the chipset drivers and the other drivers that may have been "updated" during your Windows install.
Finally, and this IMO is unlikely, make sure Windows itself is up to date. Simply reinstalling Windows doesn't get all the most recent updates.
I can say that I have the latest NVIDIA drivers and just updated to 1903 yesterday (it did it on both this new Windows version and 1809). It's definitely something software related though, because before my June re-installation of Windows, this particular thing didn't happen.
I notice it happens more when changing Noise Settings under the Filtering tab in Render Settings (especially in 4.10 Pro).
Anyone else have any suggestions? I greatly appreciate it!
I dont know the tech behind it, but that usually happens to me when I run out of memory. I monitor my task manager to see how high the render memory gets and then I kill it if it starts to top out. Not sure if that helps but thats my experience.
You mean Studio locks up and you must kill the process, or it just switches to CPU? My case is different from the usual crash to CPU. It locks up the whole program and my CPU fan gradually ramps up until I kill DAZ Studio in the Task Manager. That's a first.
I believe that was more or less what was happening with mine as well. The whole system gets so bogged down by the render that it practically locks up the pc. If I remember correctly switching to CPU means that your gpu vram has run out and the cpu has to kick in to compensate(?). What were you rendering at the time? Did you have alot of large texture files in the scene?
My issue only locks up Studio, not the whole machine. However, it's what my CPU fan does that's made this bizarre (gradually getting louder and louder every few seconds, versus just reaching a steady point like it normally does during the GPU to CPU crash). That's the part I can't figure out.
What was I doing? It seems to mainly happen during certain switches from the Viewport with Texture Shading to the AUX Viewport with Iray Shading. It has never done it during an Iray Render.
Hmmm. Yah I dont have a clue. The only wierdness that ive ever experienced with my fan was that as soon as I turned on the pc it would spool up to 100%. That was obviously a pc issue not related to daz.
Sorry I couldnt help. Good luck!
Thanks for trying though!
I might have an answer for you, but I'll need you to check for something first.
1. Grab yourself a fresh copy of GPU-Z.
2. Open it to the Sensors tab for one of your Titan Xp's.
3. Open Daz and fiddle around until you start getting the CPU spiking behavior again.
4. Switch back to GPU-Z and take a close look at the graph for "Bus Interface Load".
Is the value there jumping above 1% intermittently? Or is it staying at or below 1% throughout.
When it happens again, I'll be sure to do that and check back!
Update: So it happened again, and during that time, the Bus Interface Load stayed at 0%.
Darn. Thought it might be a sideffect of pre Cuda 6.x Unified Memory at work on the driver level. Could you post the tail end of your log file from when it happens? That may reveal what's actually going on.
ETA:
One other thing you could try - go to the Draw Settings pane with DrawStyle set to NVIDIA Iray and try playing around with the value for Drawing > Response Threshold. On my system with an extremely fast GPU (Titan RTX) having this value too low sometimes causes the Iray rendering plugin itself to crash internally (if you jerk the viewport around a lot) leading to similar behavior with the CPU to what you describe.
Funny you mention the Titan RTX, as I plan to buy two within the year (replace my Xp-s). In the meantime, I've just fully deleted and reinstalled all of my Studio stuff (although this time, I installed 4.12 from th DIM and my ZIP of 4.10 Pro). We'll see if that makes any difference! Hopefully it does, so I don't have to reinstall Windows. :P