Simulation speed between Max 2016 and 2018

[LarsSonparsson]

There is a huge difference in performance when I moved to Max 2018. In 2016 I get about 1.6M c/s and the same scene and frame in 2018 goes only 0.42M c/s max.

Max versions are not using exactly the same nightly, so the difference could be there also.

Max 2016
phoenixFD_adv_30502_max2016_vray_30_x64_27155

Max 2018
phoenixFD_adv_30402_max2018_vray_30_x64_27751

[Svetlin.Nikolov]

Hey,

Would it be possible to check against Max 2016 with nightly 27751? Also, can you send the scene which slows down?

We run performance tests daily and overall the performance has only increased since Phoenix 3.0, so it would be great if we can catch whatever cases are causing a slowdown.

A question that comes to mind is - are you using remote desktop by any chance? Max 2018's viewports got slower with the Nitrous Software renderer through Windows' remote desktop.

Cheers!

[LarsSonparsson]

Max 2018 file sent to support.

I installed 27751 to 2016 and the same performance problem is there too.

[Svetlin.Nikolov]

Great, thanks very much!

[LarsSonparsson]

Have you found time to check this?

I just sent one quite heavy simulation to network machine, which still had 27751 installed and the performance was horrible.
Frame 285 took 1.5 hours to simulate, but when I installed older version 27612, it took only 7 minutes on a same machine.
I also noticed, that when checking the average and maximum memory usage from Deadline monitor, 27751 was using at least double or more compared to 27612.

I would like to install some new nightly to get the option "expand don't shrink", but am afraid to install any new version until this is fixed.

[Svetlin.Nikolov]

Still waiting for Support to route it to us...

[Svetlin.Nikolov]

Sweet, got the scene and the slowdown is fixed! Check tomorrow's nightly build for the fix

Thanks very much for catching this!

[LarsSonparsson]

Fantastic news! Thank you!

[LarsSonparsson]

Having the same problem still...

phoenixFD_adv_30402_max2018_vray_30_x64_27771
phoenixFD_adv_30402_max2018_vray_30_x64_27774

Tested both, but the simulation still starts to slowdown dramatically at some point.

I have sent a new file to support to investigate.

[Svetlin.Nikolov]

Ahh, sorry, you mean that further in the simulation it starts getting very slow. Will take a look at this too...

[LarsSonparsson]

Yes, I just found out, that it doesn't happen in the beginning of the simulation. It just starts to slowdown at some point.
It is acting like there is a memory leak, but when it starts to slowdown, the memory usage is just about 14Gb or so.

Now I'm simulating that same scene with 27612 and the speed is ok.

[Svetlin.Nikolov]

Hmmm, if you compare the Required Ram on the Simulation rollout with 3ds max's usage in Task Manager, is there a big difference?

Also, are you restoring from a frame forward in the simulation, or starting from the beginning? I'm at 124 now - 1 min for 31M cells with SPF 2 and 16 conservation steps...

[LarsSonparsson]

I had to install the old version to workstation and simulationslaves to continue working, so I can't give you the ram usage numbers for latest versions.
With the old version using now, it shows in frame 69 Required Ram 1700MB and Ram usage for max is actually 9000MB

I start the simulation from the beginning.

[Svetlin.Nikolov]

Huh, that's with the old version? Are there any extra assets or something? I'm currently running the previous scene you sent with today's nightly and the required ram of Phoenix is about 90% of what Max uses - currently 6 gigs at frame 150.

I will let it simulate until frame 300 and then compare it to the older nightly...

[LarsSonparsson]

Yes, with the old version. No extra assets. The scene you have, has everything there is, so rest of the scene isn't that heavy.
And you are using the scene I sent you today? Burning house.