Gradual sim\viewport slowdown max 2022 flip

[Paul Oblomov]

What difference does it make? If the phoenix gives results in its units, which decrease over time. Why does he do it

Does it make no sense ?

So the phoenix is doing some meaningless thing and you know it and don't fix it ? OMG !

[Svetlin.Nikolov]

Uhm, not sure what you are talking about. Are you replying to Ivaylo or me? For sure Phoenix is not doing anything meaningless

Can you run the sim again with a latest nightly and send over the log file I asked you about? I hope this will say more about what the sources are doing.

Cheers!

[Paul Oblomov]

I just don't quite understand why counting voxels per second is a bad way to evaluate something. After all, it's clear that when it goes down every time you press the simulate button, something weird happens.

And yes, I will definitely download a new build, computer is busy right now.

[Svetlin.Nikolov]

Ah, cool, so in short:

The fire/smoke solver is grid based. It will do the same amount of calculations no matter if the grid is full of smoke or completely empty, because it will calculate the velocity field. So if you gradually fill the grid with smoke, it won't really change the simulation speed between frames. Technically it's a bit different, but overall this is what's up

The FLIP liquid solver used particles for the liquid and a grid for the velocities. So the grid takes some time and the particles take some time to calculate. You can have a huge grid full of particles and you can have the same grid with very few particles, and the few particles will be faster. E.g. if you have a grid that you fill up with liquid, the more liquid you have, the slower each frame will be.

HOWEVER, your log file shows that something entirely different happens to the source emission - it's getting progressively slower on your pc, and it seems to get slower even after you stop the sim and start it again, which is very weird and smells like something is up with the interacting geometry or the scene in general. Does not seem related to the grid/FLIP stuff above.

Hope this makes sense.

[Paul Oblomov]

I was just saying that same scene and same particles count and I think, that it is totally fine to measure performance. No ? I suppose, that there's something with underwater foam emission.

[Svetlin.Nikolov]

I suppose, that there's something with underwater foam emission.

Could be, could be...

[Paul Oblomov]

I tried

We are having technical difficulties. Please try later.

[Svetlin.Nikolov]

Say again?

[Paul Oblomov]

Hm. You did smth with phx. I don't see slowdown now

[Svetlin.Nikolov]

Yay! Maybe you hit a bad nightly before?

[Paul Oblomov]

Who knows I love nightlies! The everyday life of a beta tester...