Author Topic: The new 3000 series graphics cards from Nvidia and GPU rendering  (Read 4540 times)

2020-09-28, 19:31:45
Reply #15

danio1011

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I found the same thing: VRay GPU with one 1080 Ti for viewport and two 2080 Ti's for rendering was very responsive with IR and the interface didn't feel 'bogged' like CPU renderers can.  But the bugs, denoiser quality and lack of supported features pushed me away again.  Redshift seems to be getting better and better...

Related side note: I have noticed Max 2021.2 seems faster for me than 2020 with Corona 6.  I've also noticed (weirdly) that my 3970X is snappier with viewport and IR stuff than my 3990X.  I have two 3990's and one 3970 and my 3970 is the preferred workstation.  The frame rates are higher when running IR and it's generally more responsive.  The 3990s still beat the 3970 when it comes to production, of course!

2020-09-29, 11:04:58
Reply #16

Juraj

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Danio, how "fast", or rather slow is your 3dsMax when you run IR on both 3990X and 3970X ?

I find the whole experience terrible for some reason.. to me the whole 3dsMax UI gets so slow and laggy during IR regardless of how many CPU threads I dedicate as off. I can literally put IR to only run on 50perc. of threads and it's still very slow.
The IR itself is very fast, but just changing stuff in material editor is instantly 3 times slower than outside of IR. Clicking on modifiers, etc..

2021.2 here, but the overall experience doesn't seem any different than it did in 2016. It's like the Corona IR for me simply hogs all the I/O bandwidth of CPU regardless of utilization. I would never call it snappy, and I am on completely freshly reinstalled Windows, with all security features disabled for 3dsMax (like Real-time protection: FlowGuardControl,etc..).

I am no longer sure if I have different expectations than others or if there is indeed something wrong.

This is one massive benefit of GPU renderers, they can run on different GPUs for Viewport and Computation and the CPU cycles are fully saved for fluid work environment.
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2020-09-29, 17:50:18
Reply #17

danio1011

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Juraj - So I just did a quick test and on a super heavy scene with tons of forest pack my 3990x was dropping to 9-13fps during IR, and the 3970x was staying more around 18-23fps.  Not an exact test but relatively true to my experiences.  Even outside of 3ds Max, I find the 3970x to server me a bit better.  The 3990x would randomly 'bog' and I'd get super frustrated with it.  Pretty subjective, I know.

The backstory is I had been using my 3970x as my workstation since I built it and using the 3990x as my render node and that was working well.  But then a couple months ago I moved into a different office space and decided to switch to my 3990x into the role of workstation because I thought IR would be faster.  I then noticed things being pretty sluggish and my productivity dropping and I thought it was a bug with Corona or my windows install or something.  I did all the usual things: Control flow gaurd, real time threat, defender, nvidia drivers, etc. all done and investigated to the point of nausea.  I even started a thread on it over at 'I need help.'  For a long time it didn't occur to me it might be the different system, which in retrospect seems pretty dense on my part :-)  Eventually I connected the dots and switched back to my 3970x and bam, happy again. 

Keep in mind that's totally anecdotal and it may well be something about my build.  For example, I just built another 3990x as a render node and it runs slightly faster than my other 3990x by a few hundred mhz when used as a render node, but I think that's because the new build still has the case door off (literally just built it) and is running cooler.  I have NOT tested that new 3990x as a workstation, maybe it's just as fast as my 3970x.  ALSO, the original 3990x has 128gb of RAM, whereas my 3970x only has 64gb of ram (all running quad channel of course).

My guess is the difference I found between the 3990x and the 3970x is due to one of these:
1 - Idiosyncrasy of one of my builds causing this difference
2 - Higher core speed on 3970x helps just enough to be noticeable
3 - Something in the backend of the chips that relates to IO
4 - Windows and super high core count causing issues
5 - 64gb of ram on a third gen threadripper just runs faster than 128gb
6 - It's all in my head

I would argue #6 is the least likely, but just throwing it in there :-)  Anyway, hope those experiences are helpful!  Don't build a 3970x just because of me, but maybe you could test another chip for free somehow.

2020-09-29, 18:45:18
Reply #18

Juraj

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What I meant is like:

- I open my scene, or even fresh 3ds Max instance. Opening material, clicking on any material (even empty one) takes about...half a second to refresh the UI.
- Once I start IR, clicking on material in (compact) editor, the UI takes 2 seconds to refresh. The 3dsMax UI is sluggish, the IR runs blazingly fast (esp. with Optix).
- This sluggishness remains no matter how many cores I dedicate as "empty". For example even 50perc. of them. Since they will just run faster anyway..

If there was a way to make the IR process within 3dsMax lower priority in order of operations. But 3dsMax is single-process in task manager, so not even tools like Process Lasso can help.
I imagine if I could make 3dsMax with its bullshit SINGLE-THREAD OPERATION run at higher affinity, as top process, and Corona rendering as lower priority, might help.

Or might not :- ). Don't know. I really don't know if the issue is software (process priority) or hardware (IO). The second question could perhaps be answered by 8-channel Threadripper Pro, would be interesting if channels were mappable, not just excluding threads...but part of I/O by keeping two channels for 3dsMax, and 6 channels for Corona. Or something like that.

All those cores.. simply don't help with multi-tasking at all. Any process simply bogs down the rest of workflow of anything. I will test this comparatively on i9 and my top-tier dual 8280p xeon workstation but I expect same result.
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2020-09-29, 19:43:53
Reply #19

danio1011

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What I meant is like:

- I open my scene, or even fresh 3ds Max instance. Opening material, clicking on any material (even empty one) takes about...half a second to refresh the UI.
- Once I start IR, clicking on material in (compact) editor, the UI takes 2 seconds to refresh. The 3dsMax UI is sluggish, the IR runs blazingly fast (esp. with Optix).
- This sluggishness remains no matter how many cores I dedicate as "empty". For example even 50perc. of them. Since they will just run faster anyway..


Yes, that's the kind of thing I noticed with my 3990x as well.  Like I said, it just was slowly driving me insane :-)  Also the framerate is generally worse with IR running which I shared because I found it easier to compare fps to fps rather than just saying 'the UI is slow.'  It all adds up to a more sluggish experience and I would generally say I haven't noticed that level of sluggishness on my 3970x.  Not that it's blazing fast or anything, but I find it better.  I tried peeling off threads from my 3990x IR process using both task manager and also the Corona settings and disabling SMT (which helped a tiny bit.)  But right now I'm on my 3970x and happy, and the 3990x's are buzzing away in the other room using the awesome Pulze render manager...

Didn't you build a workstation for your modeler with a Ryzen chip?  Have you noticed anything with that machine as being less sluggish than the 3990x?  I'm truly curious now.
« Last Edit: 2020-09-29, 19:56:14 by danio1011 »

2020-10-09, 13:34:33
Reply #20

Juraj

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I did, and I had that (3950X, 128GB 3600/CL16) PC for reinstall past week. I didn't find any perceivable difference in sluggishness once I started IR to 3990X. Effectively identical behavior.
I even tested this on i9 7980X and dual-xeon 8280p. Same..

So this is imho 3dsMax/Corona limitation. Either because Windows sees it as one process(with multiple sub-processes) there can't be any affinity preference given to either process so Corona overtakes the CPU fully for itself.

I didn't mention or measure Frame rates since I am talking about UI delays, not viewport speed.
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2020-10-09, 15:25:39
Reply #21

aldola

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i use fstorm and corona regularly, gpu is very very fast but parsing times sucks, i miss the inmediacy of corona when working on fstorm, the same with vray gpu..

2020-10-26, 15:10:45
Reply #22

agentdark45

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So I stumbled across this article regarding GPU based path tracing (specifically using CUDA and OptiX): https://pharr.org/matt/blog/2020/08/19/pbrt-v4-released.html

Some interesting takeaways:

"...the GPU version runs all of the same C++ code as regular pbrt to generate camera rays, compute values for low-discrepancy sampling patterns, evaluate and sample lights and BSDFs, filter image samples—pretty much all of the core rendering computation...

And GPUs nowadays are fast… After a little performance work after HPG, now pbrt on the GPU is even faster than it was when I gave that talk. Speedups versus pbrt running on a 6 core CPU are generally 50-100x. If you feel like a 6 core CPU isn’t a fair baseline, then it’s about 10-20x faster than running pbrt on a 32-core Threadripper 3970X"

There's a video link on the page regarding the coding - this is all well above my paygrade, so maybe the devs could chime in on this? Is this some ground breaking new tech/code, or standard marketing?
Vray who?

2020-11-16, 17:33:36
Reply #23

maru

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What I meant is like:

- I open my scene, or even fresh 3ds Max instance. Opening material, clicking on any material (even empty one) takes about...half a second to refresh the UI.
- Once I start IR, clicking on material in (compact) editor, the UI takes 2 seconds to refresh. The 3dsMax UI is sluggish, the IR runs blazingly fast (esp. with Optix).
- This sluggishness remains no matter how many cores I dedicate as "empty". For example even 50perc. of them. Since they will just run faster anyway..

...

Juraj, can you check out my video below? I am curious if you are describing similar performance to this or if it's actually worse for you for some reason. I would say it's acceptable for me. I saw some examples of slow 3ds Max UI on a 3970x and I also remember how sluggish it was on a 2990wx. Maybe you could record a similar video so it would be easier to see what kind of lags you mean? 
It's 3ds Max 2021 with all updates, Corona 6 HF1, Ryzen 3900x, 2560x1440 resolution, 2 monitors, GTX 1660Ti.
https://www.dropbox.com/s/k5sfim9m8v989o3/3900x-max-speed.mp4?dl=0