Long File Load Times

Ever since I went from Rhino V6 to V7 I have encountered extremely long file load times. By that I mean taking several minutes to load. It seems random when this happens. Sometimes files open immediately. Sometimes it takes a long time. File size is not a driver. It can even happen when creating a new file. When I go into Activity Monitor, Rhino is marked in red as non responsive.

When I had raised this before it was suggested this was due to my olde OS. Now I have the new computer and latest OS and I am seeing the same thing.

Here’s a screen shot. While it take a long time, not a lot of CPU is being used.

There is something going on here. The problem is not OS. The problem is not ARM v. Intel.

I just OPENED a file and it took FIVE MINUTES to load.

I shut down Rhino, created a new file, and did IMPORT. The same file loaded in a blink of an eye.

Hello- is the (slow) file on the local hard drive or a network? Are there textures and materials on the network?


Local, SSD
No textures or materials. Just curves, surfaces, and blocks composed of surfaces.

I just did one that took five minutes to load and 1/2 a second to import.

I also see slowness when creating new files.

@miano - is this behavior consistent per file or random or?
I guess a SystemInfo output would not hurt, can you run that and post the results?


The amount of time is random but it is frequently slow.
I had slow load times on my Intel mac as well.

Rhino 7 SR23 2022-10-9 (Rhino 7, 7.23.22282.13002, Git hash:master @ a931168ca9426920ae6aa97218710b662f17fc39)
License type: Commercial, build 2022-10-09
License details: Cloud Zoo

Apple macOS Version 12.2.1 (Build 21D62) (Physical RAM: 64Gb)
Rhino is running in Rosetta2 on Apple Silicon
Mac Model Identifier: MacBookPro18,2
Language: en-US (MacOS default)

Apple M1 Max (OpenGL ver:4.1 Metal - 76.3)

OpenGL Settings
Safe mode: Off
Use accelerated hardware modes: On
Redraw scene when viewports are exposed: On

Anti-alias mode: 4x
Mip Map Filtering: Linear
Anisotropic Filtering Mode: High

Vendor Name: Apple
Render version: 4.1
Shading Language: 4.10
Maximum Texture size: 16384 x 16384
Z-Buffer depth: n/a
Maximum Viewport size: 16384 x 16384
Total Video Memory: 48 GB
Graphics: Apple M1 Max
Displays: Unknown (255dpi 2x)

Graphics processors
Apple M1 Max
Color LCD (1728 x 1117 @ 120.00Hz)

USB devices

Bluetooth devices

Third party kernel extensions

Third party plugins

Rhino plugins that do not ship with Rhino

Rhino plugins that ship with Rhino
/Applications/Rhino 7.app/Contents/Frameworks/RhCore.framework/Resources/ManagedPlugIns/RhinoCycles.rhp “RhinoCycles” 7.23.22282.13002
/Applications/Rhino 7.app/Contents/PlugIns/NamedSnapshots.rhp “Snapshots” 7.23.22282.1002
/Applications/Rhino 7.app/Contents/Frameworks/RhCore.framework/Resources/ManagedPlugIns/GrasshopperPlugin.rhp “Grasshopper” 7.23.22282.13002
/Applications/Rhino 7.app/Contents/PlugIns/PanelingTools.rhp “PanelingTools” 7.23.22282.1002
/Applications/Rhino 7.app/Contents/PlugIns/AnimationTools.rhp “AnimationTools” 7.23.22282.1002
/Applications/Rhino 7.app/Contents/Frameworks/RhCore.framework/Resources/ManagedPlugIns/Commands.rhp “Commands” 7.23.22282.13002
/Applications/Rhino 7.app/Contents/Frameworks/RhMaterialEditor.framework “Renderer Development Kit” 7.23.22282.1002
/Applications/Rhino 7.app/Contents/Frameworks/RhCore.framework/Resources/ManagedPlugIns/RDK_EtoUI.rhp “RDK_EtoUI” 7.23.22282.13002
/Applications/Rhino 7.app/Contents/PlugIns/Displacement.rhp “Displacement” 7.23.22282.1002
/Applications/Rhino 7.app/Contents/Frameworks/RhCore.framework/Resources/ManagedPlugIns/RhinoRenderCycles.rhp “Rhino Render” 7.23.22282.13002
/Applications/Rhino 7.app/Contents/Frameworks/RhCore.framework/Resources/ManagedPlugIns/RhinoDLR_Python.rhp “IronPython” 7.23.22282.13002
/Applications/Rhino 7.app/Contents/PlugIns/RhinoRender.rhp “Legacy Rhino Render” 7.23.22282.1002

Your macOS is several updates behind.
I believe 12.6 is current.
That’s the “low hanging fruit” here.

Any luck?

But, is the slowness per file? Does the same file always load slowly, however slow that is, and other files always load normally? If the slowness is consistently per file, it would be best if we could get one of those.


I uploaded a file exactly as I was working on it. That file takes about 4-5 minutes to OPEN but imports instantly on my system.

Hello- can you please try
Import the file
Open this saved file - is that fast or slow?

(Here your file opens and imports in about the same amount of time - 5-10 seconds, at a guess. )


I had tried that several times already. The saved file is slow opening----but each import is lightning fast!

Another thing to try:

  • Quit Rhino completely.
  • Start Rhino
  • Open the slow file, not touching Grasshopper in any way.

Any different?


No, but it gets a bit faster after a complete reboot.

I am seeing this on my new ARM Mac as well. It can take several minutes to load even the smallest of files. Sometimes it can be reasonably fast.

Right now I am staring at a 3.5MB file that has been loading for 3 minutes. In this case it’s from a network drive but I get this slow behavior on my local SSD as well.

Is there anything to do to diagnose this? Right now 10 minutes to load 3.3MB file.

No consistency as to when it happens.

I have always suspected file versioning is at the heart of the problem.

We could try taking a look at the file. Did you ever send this file in to tech support to take a look at?

It can happen with any file at random times. A 3mb file can take 2 seconds one time and 10 minutes another.

Is there any way to help diagnose this problem? I am finding it frequently and only in Rhino. It takes a system reboot to clear. Or I can wait a long time for the file to load. After a reboot, the load times return to normal for a while. There is obviously some operating system interaction involved.

I saw this problem on my olde Intel Mac starting in V7 and I still see it on my ARM Mac.

We’re going to need to see a file to reproduce this one. Either an example attached to a reply here or - if the file is big or confidential - then it can be uploaded to Rhino - Upload to Support

We’d love to take a look if you’re still experiencing this problem.