Maniphest T76117

Smooth Modifer Crash - TDR
Closed, Archived
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Assigned To
Brecht Van Lommel (brecht)
Authored By
Philip Holzmann (Foaly)
Apr 26 2020, 9:44 AM
Tags
  • BF Blender
  • Modifiers
Subscribers
Brecht Van Lommel (brecht)
Germano Cavalcante (mano-wii)
Philip Holzmann (Foaly)
Richard Antalik (ISS)

Description

System Information
Operating system: Windows 10 64 bit
Graphics card: Nvidia GTX 750 Ti

Blender Version
Broken: blender-2.83 beta 76b3aac802f9 or 47ae0affc8f29df92c82f2a9580b58f84819df7d master Fri Apr 24 11:34:04 2020 +0200

Short description of error
When the smooth modifier is applied with "crazy" values on some high poly meshes, it can crash randomly.

Checked the windows logs, and I guess a gpu timeout is what it is.

A TDR has been detected.
The application must close.

Error code: 7
 (pid=2248 tid=6436 blender.exe 64bit)

Visit http://nvidia.custhelp.com/app/answers/detail/a_id/3633 for more information.

Exact steps for others to reproduce the error

smooth01.blend2 MBDownload

Slide the factor slider back and forth.
Sometimes it crashes immediately, sometimes it takes a few times.

Related Objects

Mentioned Here
rB76b3aac802f9: Fix T75842: GPencil Edit mode of unselected object is visible
rB47ae0affc8f2: Depsgraph: Use BLI::Map instead of GHash for operations_map

Event Timeline

Philip Holzmann (Foaly) created this task.Apr 26 2020, 9:44 AM
Germano Cavalcante (mano-wii) added a subscriber: Germano Cavalcante (mano-wii).Apr 28 2020, 2:23 PM

I slided the factor back and forth several times but I couldn't reproduce the crash.
Could it be that you are running out of memory?
While we want to improve Blender to handle such cases memory gracefully, this is not currently considered a bug.

Richard Antalik (ISS) changed the task status from Needs Triage to Confirmed.Apr 28 2020, 7:26 PM
Richard Antalik (ISS) added a subscriber: Richard Antalik (ISS).

I got not responding situation here, pausing in debugger refused to show me anything.

I guess we could consider this known issue at least if this is caused by some "GPU hangup while process is waiting" situation that is hard to sanitize.

Though I am not sure what exactly is happening in this case.

Germano Cavalcante (mano-wii) added a comment.Apr 28 2020, 7:33 PM
In T76117#919457, @Richard Antalik (ISS) wrote:

I got not responding situation here, pausing in debugger refused to show me anything.
...

The object being smoothed is extremely high poly, it is to be expected that the CPU takes time to compute all operations.
That's why I tested it in Release build.

Richard Antalik (ISS) added a comment.Apr 28 2020, 9:49 PM

I have tested in release with debug info which usually give profiler data with no problems, but this time it gave up. also if I paused execution it showed only [external code].

Philip Holzmann (Foaly) added a comment.Apr 29 2020, 7:15 AM

@Richard Antalik (ISS) Did it actually crash for you when not using a debugger?

Also, it occured to me to check the windows logs, and I guess a gpu timeout is what it is.

A TDR has been detected.
The application must close.

Error code: 7
 (pid=2248 tid=6436 blender.exe 64bit)

Visit http://nvidia.custhelp.com/app/answers/detail/a_id/3633 for more information.

This is unfortunate.
I believe if the smooth factor becomes too big (i.e. far greater than 1.0), the triangles become so big that they cause so many fragments to be rendered that the gpu timeouts.
I guess this could be mitigated by making 1.0 (or 2.0) a soft maximum for the factor slider, to prevent accidentally entering a huge value (which has happened to me).

Richard Antalik (ISS) added a comment.Apr 29 2020, 7:18 PM
In T76117#919767, @Philip Holzmann (Foaly) wrote:

@Richard Antalik (ISS) Did it actually crash for you when not using a debugger?

Technically not crash. but Blender become unresponsive.

Also, it occured to me to check the windows logs, and I guess a gpu timeout is what it is.

A TDR has been detected.
The application must close.

Error code: 7
 (pid=2248 tid=6436 blender.exe 64bit)

Visit http://nvidia.custhelp.com/app/answers/detail/a_id/3633 for more information.

Thanks for info.

I guess this could be mitigated by making 1.0 (or 2.0) a soft maximum for the factor slider, to prevent accidentally entering a huge value (which has happened to me).

Perhaps. I think, It is not ideal to change limits blindly if you can not guarantee that they will work.

Richard Antalik (ISS) renamed this task from Smooth Modifer Crashes Randomly to Smooth Modifer Crash - TDR.Apr 29 2020, 7:19 PM
Richard Antalik (ISS) updated the task description.
Richard Antalik (ISS) added a project: Modifiers.
Brecht Van Lommel (brecht) closed this task as Archived.May 1 2020, 6:25 PM
Brecht Van Lommel (brecht) claimed this task.
Brecht Van Lommel (brecht) added a subscriber: Brecht Van Lommel (brecht).

There is not a lot we can do about TDRs, they are hard to predict and once they happen it's fully up to the graphics driver to recover from them.

GPUs are just very slow at rendering many large overlapping triangles.