Geometry nodes/modifiers: separate system influence to another GN performance (like invisible link). Performance drop #102327

New Issue

Vyacheslav Kobozev · 2022-11-07T12:08:53+01:00

2022-11-07 12:08:53 +01:00

System Information
Operating system: Windows-10-10.0.17763-SP0 64 Bits
Graphics card: NVIDIA GeForce RTX 3060/PCIe/SSE2 NVIDIA Corporation 4.5.0 NVIDIA 512.95

Blender Version
Broken: version: 3.3.1, branch: master, commit date: 2022-10-04 18:35, hash: b292cfe5a9
3.2 is broken too

Short description of error
There are three systems with Suzannas. All have GN modifiers.
If one of them enabled, that drops fps and performance for other systems.
If only another (blue, identical!) system enabled, it will not influence on green`s performance and fps.

Open file, drag factor for green suzanna on curve.
It is slow.
Disable modifiers on red suzanna, green will follow curve with good fps, if you will drag factor again
But blue suzanna have full copy of red`s modifiers. And it do not influence to all others.

Important! «Nurbs path.001» was copied from «Nurbs path», and «Follow curve w» modifier was copied from «Follow curve» modifier.
But blue suzanna made with shift A, and its modifier was not copied as modifier, but modifier was created from scratch and nodes was copied from red to blue.
So there is somwhere invisible link, that bonds green to red and force to recalculate it!

follow.blend
2022-11-07_13-42-08.mp4

2022-11-07_13-53-32.mp4

**System Information** Operating system: Windows-10-10.0.17763-SP0 64 Bits Graphics card: NVIDIA GeForce RTX 3060/PCIe/SSE2 NVIDIA Corporation 4.5.0 NVIDIA 512.95 **Blender Version** Broken: version: 3.3.1, branch: master, commit date: 2022-10-04 18:35, hash: `b292cfe5a9` 3.2 is broken too **Short description of error** There are three systems with Suzannas. All have GN modifiers. If one of them enabled, that drops fps and performance for other systems. If only another (blue, identical!) system enabled, it will not influence on green`s performance and fps. Open file, drag factor for green suzanna on curve. It is slow. Disable modifiers on red suzanna, green will follow curve with good fps, if you will drag factor again But blue suzanna have full copy of red`s modifiers. And it do not influence to all others. Important! «Nurbs path.001» was copied from «Nurbs path», and «Follow curve w» modifier was copied from «Follow curve» modifier. But blue suzanna made with shift A, and its modifier was not copied as modifier, but modifier was created from scratch and nodes was copied from red to blue. So there is somwhere invisible link, that bonds green to red and force to recalculate it! [follow.blend](https://archive.blender.org/developer/F13864201/follow.blend) [2022-11-07_13-42-08.mp4](https://archive.blender.org/developer/F13864172/2022-11-07_13-42-08.mp4) [2022-11-07_13-53-32.mp4](https://archive.blender.org/developer/F13864195/2022-11-07_13-53-32.mp4)

Vyacheslav Kobozev commented

2022-11-07 12:08:53 +01:00

Added subscriber: @Vyach

Omar Emara commented

2022-11-08 15:11:24 +01:00

Added subscriber: @OmarEmaraDev

Omar Emara commented

2022-11-08 15:11:24 +01:00

I can't notice any significance in FPS in either cases, but that might be because my viewport is already very slow. So I will leave this to someone else.

Vyacheslav Kobozev commented

2022-11-09 06:29:15 +01:00

In #102327#1442594, @OmarEmaraDev wrote:
I can't notice any significance in FPS in either cases, but that might be because my viewport is already very slow. So I will leave this to someone else.

Try to drop subdivisions on green (to 4-5) and disable modifiers on red suzanna or even delete it. Anyway thanks for try

> In #102327#1442594, @OmarEmaraDev wrote: > I can't notice any significance in FPS in either cases, but that might be because my viewport is already very slow. So I will leave this to someone else. Try to drop subdivisions on green (to 4-5) and disable modifiers on red suzanna or even delete it. Anyway thanks for try

Germano Cavalcante commented

2022-11-09 20:14:14 +01:00

Added subscriber: @mano-wii

Germano Cavalcante commented

2022-11-09 20:14:14 +01:00

Changed status from 'Needs Triage' to: 'Confirmed'

Germano Cavalcante commented

2022-11-09 20:14:14 +01:00

I can confirm the problem.

My guess is that since the Suzanne object was referenced in the Object Info node before it was plugged into the Group Input, it continues to be referenced in the modifier even after it has been removed.

This creates a false dependency.

So it's probably a side effect of the same bug reported in #101615 (Geometry Nodes Object Group input does not remove dependencies).

But I'm confirming it as a separate bug since I'm not sure.

I can confirm the problem. My guess is that since the Suzanne object was referenced in the `Object Info` node before it was plugged into the `Group Input`, it continues to be referenced in the modifier even after it has been removed. This creates a false dependency. So it's probably a side effect of the same bug reported in #101615 (Geometry Nodes Object Group input does not remove dependencies). But I'm confirming it as a separate bug since I'm not sure.

Richard Antalik commented

2022-11-09 20:28:11 +01:00

Added subscribers: @HooglyBoogly, @iss

Richard Antalik commented

2022-11-09 20:28:11 +01:00

I am able to reproduce, but not quite sure how the problem was created. this may be information we need to resolve the issue.

Will CC @HooglyBoogly in meanwhile. I am not sure if there is bug or not especially without steps since I am not very familiar with GN in its details.

From what I understand steps to test are :

Select object NurbsPath
Tweak Factor input of geometry nodes (should be fast)
Select object Suzanne.001
Enable Subdivision modifier
Select object NurbsPath
Tweak Factor input of geometry nodes (should be fast, but it's slow)

I am able to reproduce, but not quite sure how the problem was created. this may be information we need to resolve the issue. Will CC @HooglyBoogly in meanwhile. I am not sure if there is bug or not especially without steps since I am not very familiar with GN in its details. From what I understand steps to test are : - Select object NurbsPath - Tweak Factor input of geometry nodes (should be fast) - Select object Suzanne.001 - Enable Subdivision modifier - Select object NurbsPath - Tweak Factor input of geometry nodes (should be fast, but it's slow)

Iliya Katushenock commented

2022-11-09 20:36:30 +01:00

Added subscriber: @mod_moder

Iliya Katushenock commented

2022-11-09 20:36:30 +01:00

This is not a regression
In the example file, just a bunch of objects has users that I couldn't find. I also tried to figure out how to print the dependency graph (I didn’t figure it out to understand who causes the lags. But the dependencies in this file are very strange)

This is not a regression In the example file, just a bunch of objects has users that I couldn't find. I also tried to figure out how to print the dependency graph (I didn’t figure it out to understand who causes the lags. But the dependencies in this file are very strange)

Hans Goudey commented

2022-11-09 20:41:29 +01:00

Closed as duplicate of #101615

Hans Goudey closed this issue

2022-11-09 20:41:29 +01:00

Germano Cavalcante referenced this issue

2023-12-22 03:07:38 +01:00

Inactive geometry dependencies preventing snapping between objects #113087

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