Allocating RAM - constant crash. Adaptive grid

[Paul Oblomov]

Can it be that 256GB is not enough for 2billion cells ? It is not expanding much, with limits and max cells set to 2 234 727 845

Should I try turning adaptive grid off and continue ?

[GRID: 2 114 171 325 cells, 1085x2385x817]
- Liquid/Temperature (300.00 : 1497.00)
- Smoke (0.00 : 1.00)
* Simulated with Phoenix 4.30.01 Nightly, Build ID: 2021032330676 for 3ds Max 2021 from Mar 23 2021

sim step 438 t:14.600001, lastFrameDuration 375.876260
Simulation stage (00)
Enter transferCtrlToMainThread: 1
transferCtrlToMainThread simEventType set: 1
etPreNewStep
notifyPreNewStep 0 0.000000
notifyPreNewStep 1 0.000127
End transferCtrlToMainThread: 1
Simulation stage (01)
Simulation stage (02)
Simulation stage (03)
new adapt size 1085 2426 947
expanding grid 0 0 0 0 5 0.
expandGridPrealloc

Now, it is quite strange to me also - load and restore makes strange things. Load and restore backup frames makes weird, scaled by Z grid

[Paul Oblomov]

Interesting enough - in max 2022 phx allocates at max 192gb. In 2021 - 259....

[Svetlin.Nikolov]

Can it be that 256GB is not enough for 2billion cells ? It is not expanding much, with limits and max cells set to 2 234 727 845)

Since this is a fire/smoke simulation and you don't have any particles, make a simulator with the exact same settings and set its resolution to e.g. 20 million voxels and measure how much ram it uses, and then just multiply it by 100. Depending on the settings you use it will be using different amounts of RAM, so this way you will know for sure if RAM is enough.

[Svetlin.Nikolov]

Interesting enough - in max 2022 phx allocates at max 192gb. In 2021 - 259....

The adaptive grid code does not really care about the Max or Maya version. Maybe you are using the Max Memory % option and you are running the simulation with different amount of free memory on the machine?

[Svetlin.Nikolov]

Now, it is quite strange to me also - load and restore makes strange things. Load and restore backup frames makes weird, scaled by Z grid

It work fine here with a simple scene. Maybe it's specific to your scene or cache?

[georgi.zhekov]

Now, it is quite strange to me also - load and restore makes strange things. Load and restore backup frames makes weird, scaled by Z grid

May be you used the Load&Start option instead of the Restore one. When using the Load&Start the loaded grid will be resized to fit the grid's dimensions at the Start Frame.

You can find more about the Load&Start option here - https://docs.chaosgroup.com/display/...lation-Actions

[Paul Oblomov]

I just deleted 2022. Pure mess. Again. Why they can't make bug free release at start. I wish I could use h as modeling tool, to finally uninstall all the adsk mess from my pc.

About the allocation - I maybe try again when they release sp, as you can't use grid preview (smth more, than a 1x1x1) with new qt ui as it lags. Whole 3dsmax lags like a piece of sh.... So disappointing.

phx is trying to allocate RAM for the grid 1085x2426x947 (2 492 702 870 cells), while the limits were set to 2 234 727 845 -> and max crashes. While I'm not sure, it can be predicted, that 257 975 025 cells won't fit in, can it be a lil be safer on that ? I saw some overhead over the RAM Working set, when phx moves to the next frame (like 40Gb - from 130gb -> 170). Next frame is not 170Gb btw.

[Svetlin.Nikolov]

It can be predicted and we're doing it all over the place, so there must be something we're missing... Let's confirm - you hit Load & Start when it runs out of memory, right?

[Paul Oblomov]

No. Just pure sim. No load and restore. I tried to figure out, how to complete my sim, so was asking about ways of doing that. I can upload restore somewhere, but I know how you don't like sit and wait, till it crash

[Svetlin.Nikolov]

Well, send over the Phoenix log and a crash dump? This will shed some light on the issue. Also I need your exact Phoenix version from the About box, or the crash dump will be useless.

[Paul Oblomov]

Hm, I turned off .dmp generation. Part of log was at the top of the topic with exact place, where it ended + also phx version. You sure dmp will help ?

[Svetlin.Nikolov]

There is nothing in this world anyone can be sure about Often dumps can show exactly where it crashed in the code, so with some guesswork we can figure out a fix. Sometimes dumps show no useful info. Still, it's better than nothing.

[Paul Oblomov]

Ok. But it will take some time