2080ti vs 1080ti : almost no performance upgrade for TFD simulation?

Technical
#1

Well, everything’s in the title…. I have 2 of both cards in my setup, ran the exact same simulation twice on each card, so 8 runs in total :
1080ti : 44min and 52secs (average, one of the cards is primary display)
2080ti : 43min and 18secs (average, computing cards)

It is also worth mentioning that GPU load during the simulation is quite low, 15-20% on average on the 1080ti, rarely peaking around 45%, 11-14% on the 2080, didn’t see it peak past 20%.
Is this underexploitation normal ? I mean, in the TFD optimization guideline I read it is advised to have 2 gpus, a weaker one as primary display and a stronger one for computing…… this does make sense in a gpu renderer…. for instance, I use redshift and in some scenes the rendertimes are actually smaller when I do NOT use my primary display card for rendering. However, with TFD only using 10-20% of the card…… I tried using my display 1080ti and my computing 2080ti and got almost no difference.

I plan on swapping my 2nd (computing) 1080ti for a 3090 (when they are available again), this sure will help with redshift but…. from the looks of it i suspect this won’t help TFD in any way other than increased VRAM :frowning:

For the records, I’m using :
last TFD version v1-0_1465
C4D R23
up-to-date Nvidia Studio drivers 461.40

Problem with Simulating with GeForce RTX 2080 Ti
#2

I shall leave this one for The Guru as I really do not have have any experience with the 2000 series. My 1070 is just about as fast as my Titan for simming but with the extra 4 GB RAM on the Titan I always use that. I do however regularly go well over 12 GB in sims so fall back to the CPU and as I am quite a fan of Arnold I think my priority will be to get more CPU power. Arnold can render TFD on the GPU if converted to vdb but I find the workflow so straightforward I tend to stick with CPU rendering. It just sits so well with TFD for shading. bcf files are a big slowdown for RS and you really need to convert to vbd to get them to render at a reasonable rate, Arnold plays with bcf very well.

#3

As an aside…it cannot be easy coding this to work on the GPU’s for simming, no other sim software can do it…not even FumeFX

#4

Could you provide a log file for simulation of a few frames on each GPU? You can attach it here or send it to support@jawset.com.
Please make sure you run the sims first, then send the file %APPDATA%\jawset\turbulence.log. This log file has detailed timings that will help to identify the bottleneck.

A possible caus is that either cache storage or complex C4D-side animation is slow enough that the GPUs are waiting for these stages to complete. A good test scene for a quick benchmark is the oil_well.c4d example scene from the plugin package. You can also run this scene in interactive mode to disable the cache.

#5

What are you using to monitor GPU usage ?. Task manager is useless…use GPU-Z

#6

Task Manager works if you select the CUDA graph:

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#7

True forgot that so used to having GPU-Z up !!

#8

But it does not show utilization accurately

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#9

Thank you Jascha for your input. I’m in the middle of a production rush right now but I’ll dive into these tests / benchmarks asap and come back to you.
Like Paul, I tend to use GPUz to monitor gpu usage, seems to me to be more accurate than task manager.