V-Ray 5 - Crashes on Mac Pro when using all 28 cores

[OhGott]

Hi there,

V-Ray 5 on a fresh C4D S22 install on my old Mac Pro 2013 with 8 Cores runs flawless.

On a fresh C4D S22 install on the a new Mac Pro 2019 with 28 Core it crashes immediately when I hit the IPR or Render button.

V-Ray doesn't crash, when I reduce the number of cores in the preferences.
I would love to use all my cores

Has the new V-Ray been tested in this configuration?

Here is a screen recording with all system information included showing the behaviour:
https://streamable.com/ejivde

Please let me know if you need the crash report or something else.

Many thanks.

Hannes


Also there are no problems with V-Ray 3.7 using all cores.

[shaio]

Hi OhGott ,
that is an interesting find. What is the amount of cores that V-Ray stops crashing when you start rendering and does it crash with Interactive only? This could be very useful info when I try to reproduce the issue. Can you please share your macOS version as well?

[deyan.hadzhiev]

Also could you try disabling the material previews from the V-Ray preferences?

[OhGott]

Hi shaio and deyan.hadzhiev,

Thanks for looking into this.

I'm running macOS Catalina latest 10.15.7 (19H114)
Big Sur is a no-go atm.

I disabled the material previews in the V-Ray preferences with no luck.
Material preview get black, but V-Ray still crashes when uncheck the custom render threads checkbox. IPR and Production Render (bucket)

I started increasing the render threads in the prefs. by 2

The strange thing is, that I was able to increase the render threads to 32. Beyond this I get crashes.
Are these settings in C4D logical threads? Having 28 physical cores means 56 logical threads?

The crash also occurred on time at 28 threads.
It doesn't feel like the problem behaves always the same.

The only stable reproducible failure ist when I uncheck the custom render threads checkbox.
Then I get a sudden crash. Regardless if IPR or Production Render (bucket).

Let me know if I can support you with more information.

Thanks.

[OhGott]

Hi shaio deyan.hadzhiev ,

today I did some detailed testing about the V-Ray crashes.

Intel Xeon 3275M 28core

V-Ray material previews disabled
- unlimited render threads -> crash
- custom set render threads to max. 50. Beyond that I get crashes

V-Ray material previews enabled
- unlimited render threads -> crash
- custom set render threads to max. 24. Beyond that V-Ray crashes

Tested with IPR and Bucket Render.

So if I need material previews I will be limited to 24 threads until a fix.
Do you have any plans to look into this any time soon?

Thanks.

[OhGott]

I did some further testing. Even with the limitation of the render threads I get random crashes. V-Ray 5 on the old Mac Pro 2013 8core runs very stable and smooth. But on the new Mac Pro 2019 28core it's unusable doe to the crashes. Both machines have the same OS and C4D version. That's sad.

[sirio76]

Hi, you may want to try to re-seat your CPU, even a slight difference when you tighten the screws can lead to problems.

[OhGott]

Hi, you may want to try to re-seat your CPU, even a slight difference when you tighten the screws can lead to problems.

Hi Sirio,

I will give it a try, but I don't have any crashes with all other applications, also not with V-Ray 3.7. I'm pushing the machine to it's limits with all other stuff I'm doing. So I guess the CPU works fine. I also did extensive hardware tests with no errors or instability. Hmm.. I' wondering if V-Ray 5 has been tested with a similar hardware configuration.

Did you managed to upgrade your machine in the meantime with a 28core CPU?

[sirio76]

I don't think Vray5 needed to be tested on every configuration since a CPU with the same architecture should work no matter if you have 8, 16 or 28core. Here on my 8core I have no issues, I was about to upgrade to a 28core for Christmas but after I've seen this topic I decided to wait a bit more. You can ask on Macrumors forum if someone can download Cinema and Vray demo version in order to test a scene and see if they get the same crashes. If someone else with a 28core can reproduce your issues then you can contact developers to see if there's something specific about that CPU.

[OhGott]

I totally agree with you that V-Ray 5 doesn't need to be tested on every configuration.

My question to the developers deyan.hadzhiev was, if it has been tested on a similar Mac OS configuration with more than 8 cores.
Let's say if it has been tested on MacOS with 12, 16, 24 or 28 cores without any issues, then the problem might be on my end.

But anyways, today I did re-tighten the screws of the heatsink as suggested. Both screws are absolutely evenly tightened. I did comprehensive tests. Everything works fine beside V-Ray 5.

Some users on Macrumors forum, which upgraded their Mac Pro 7.1 CPU had issues because of a bad instalment of the cpu heatsink. The problems they experienced where sudden crashes and shutdowns of the OS.

In my case this is not the case! Only V-Ray 5 crashes randomly the application. Not the whole computer.

What makes me wonder thinking about the problems are based on a faulty CPU or instalment on my side is, that I have absolutely no issues with all the other applications I'm running.
My setup is absolutely stable with everything else I'm doing when using multi core processes.

No issues with:
- Massive batch exports from Lightroom
- Various Photoshop filters on large files
- Cinema 4D S22 Physical Render
- Cinema 4D S22 V-Ray 3.7
- Cinebench R23
- V-Ray Benchmark 5.02
- V-Ray 5 Standalone

For now I reduced the render treads in the prefs to 8 and everything is stable.
When I "free" the cores C4D crashes immediately. But not the machine.

Before I go the route asking a member on Macrumors forum to test for me V-Ray 5, I would love to know if Chaos Group developers can say anything about their testing environment on MacOS.

[sirio76]

Let me know, I'm interested in this as well, I hope you can solve so that I can upgrade the CPU
Happy 2021!

[michael_olssson]

Hello. This might not be your issue at all but I have a new mac pro 16 core. I can't do anything with vray 5 on it if I'm not updating the C4D license. So every time I restart C4D I have to got to Help/ License Manager/ right klick the green box and choose update. Then It works. Eaven though I get a freeze every 10 minutes for 30 seconds. very stressfull.

[OhGott]

Hello. This might not be your issue at all but I have a new mac pro 16 core. I can't do anything with vray 5 on it if I'm not updating the C4D license. So every time I restart C4D I have to got to Help/ License Manager/ right klick the green box and choose update. Then It works. Eaven though I get a freeze every 10 minutes for 30 seconds. very stressfull.

I stoped working with vray for now and moved to arnold. I need a stable production environment. V-Ray 5 is very promising and I definitely will try it in a few month when it's more stable and offers more functionality.

[deyan.hadzhiev]

Hi OhGott, we found a possible cause for the crashes on Mac with more threads, that is related to the default Mac limitations for open file descriptors. Can you share the output of the following two commands executed in a terminal (they only check the current file limit per process and process count limits):

ulimit -n
ulimit -u

[OhGott]

Hi deyan.hadzhiev , thanks for looking into this.

The current output is:

256
11136

I don't know the values of the time I had crashes, because I did a complete new system install after that.
I didn't try V-Ray 5 since then, because of limited available time.

Are the above numbers good?

Thanks.