Rhino 8 Mac – RAM Usage Keeps Increasing, Even When Idle

Rendering
1

Hello,

I’m running Rhino 8 on a MacBook Pro 16” (M3 Max, 36 GB RAM) with macOS Sonoma 14.6.1.

In the past weeks I started receiving repeated warnings from macOS that my system is running out of memory, and Activity Monitor shows Rhino using 50–80 GB of RAM. This happens even when:

Rhino is just running in the background (no files open, not rendering, no Raytraced mode)

  • Only a single “Physically Based” material with HDRI environment is in use

  • No heavy textures are applied

I’ve been using Rhino on this machine for almost two years, often with larger projects, and this problem never occurred before. Other 3D apps like Blender do not show similar memory usage.

Observed behavior:

  • When I open a ~150 MB file, Rhino initially uses ~1.4–2.5 GB of RAM.

  • After about 30 minutes of very light work, memory grows to ~4.5 GB.

  • Closing the file does not release memory. Only quitting and restarting Rhino resets it back to ~1.5 GB.

  • If Rhino is left running, memory usage keeps climbing until macOS issues “out of memory” warnings.

This strongly suggests a memory leak in Rhino 8 for Mac.

Questions:

  1. Is this a known issue in Rhino 8 for Mac?

  2. Is there a patch or service release that addresses it?

  3. Are there recommended workarounds (e.g., disabling certain display modes, clearing undo, avoiding Physically Based materials, etc.) until a fix is available?

Thanks very much for your support,

Ondrej

2

I’m pretty sure the experts will need you to run Rhino’s Systeminfo command and copy and paste the text output from it here.

2 Likes
3

To answer any and all of your questions, as @AlW says we’d need a SystemInfo and ideally any file you’re comfortable sharing to start diagnosing this. If you’re not okay sharing it here, you can upload it here confidentially.

The only thing I can suggest to start is to try running Rhino without any plugins. This guide may help. It suggests deleting the plugins folder, but you could also rename it to plugin_bak temporarily and restore it as needed.

1 Like
4

Hello,
thanks for answering my post.
btw, I am not using any 3rd party plugins…

Here is required system info:
Please let me know.

Rhino 8 SR23 2025-9-8 (Rhino 8, 8.23.25251.13002, Git hash:master @ e75a9d62e23cc6f52d4ef68eb7eda9f8da9b6cd9)

License type: Commercial, build 2025-09-08

License details: Cloud Zoo

Apple macOS Version 14.6.1 (Build 23G93) (Physical RAM: 36GB)

Mac Model Identifier: Mac15,11

Language: en

.NET 8.0.14

Metal GPU Family Apple 7

Metal GPU Family Common 3

Metal GPU Family Mac 2

Graphics processors

Apple M3 Max

Color LCD (1728 x 1117 @ 120.00Hz)

GPU Vendor: Apple

USB devices

None

Bluetooth devices

None

Third party kernel extensions

None

Third party plugins

/usr/lib/swift/libswiftCore.dylib

/usr/lib/swift/libswiftCoreFoundation.dylib

/usr/lib/swift/libswiftCoreGraphics.dylib

/usr/lib/swift/libswiftCoreImage.dylib

/usr/lib/swift/libswiftDarwin.dylib

/usr/lib/swift/libswiftDispatch.dylib

/usr/lib/swift/libswiftIOKit.dylib

/usr/lib/swift/libswiftMetal.dylib

/usr/lib/swift/libswiftOSLog.dylib

/usr/lib/swift/libswiftObjectiveC.dylib

/usr/lib/swift/libswiftQuartzCore.dylib

/usr/lib/swift/libswiftUniformTypeIdentifiers.dylib

/usr/lib/swift/libswiftXPC.dylib

/usr/lib/swift/libswift_Concurrency.dylib

/usr/lib/swift/libswiftos.dylib

/usr/lib/swift/libswiftsimd.dylib

/usr/lib/swift/libswift_StringProcessing.dylib

/usr/lib/swift/libswift_RegexParser.dylib

/usr/lib/swift/libswiftCryptoTokenKit.dylib

/usr/lib/usd/libusd_ms.dylib

/usr/lib/swift/libswiftCoreAudio.dylib

/usr/lib/swift/libswiftCoreLocation.dylib

/usr/lib/swift/libswiftCoreMedia.dylib

/usr/lib/swift/libswiftCompression.dylib

/usr/lib/swift/libswiftCoreMIDI.dylib

/usr/lib/swift/libswiftAVFoundation.dylib

/usr/lib/swift/libswiftCoreML.dylib

/usr/lib/swift/libswiftFileProvider.dylib

/usr/lib/swift/libswiftIntents.dylib

/usr/lib/swift/libswiftAccelerate.dylib

/usr/lib/swift/libswiftGLKit.dylib

/usr/lib/swift/libswiftGameplayKit.dylib

/usr/lib/swift/libswiftMetalKit.dylib

/usr/lib/swift/libswiftModelIO.dylib

/usr/lib/swift/libswiftSceneKit.dylib

/usr/lib/swift/libswiftSpriteKit.dylib

/usr/lib/swift/libswiftVision.dylib

/usr/lib/swift/libswiftRegexBuilder.dylib

/usr/lib/swift/libswiftDemangle.dylib

/usr/lib/swift/libswiftShazamKit.dylib

/usr/lib/swift/libswiftObservation.dylib

/usr/lib/swift/libswiftVideoToolbox.dylib

/usr/lib/swift/libswiftWebKit.dylib

/usr/lib/swift/libswiftNaturalLanguage.dylib

/usr/lib/swift/libswiftSystem.dylib

/usr/lib/swift/libswiftMapKit.dylib

/usr/lib/swift/libswiftFoundation.dylib

/usr/lib/log/liblog_network.dylib

Rhino plugins that do not ship with Rhino

Rhino plugins that ship with Rhino

/Applications/Rhino 8.app/Contents/Frameworks/RhMaterialEditor.framework “Renderer Development Kit” 8.23.25251.1002

/Applications/Rhino 8.app/Contents/Frameworks/RhCore.framework/Resources/ManagedPlugIns/Commands.rhp “Commands” 8.23.25251.13002

/Applications/Rhino 8.app/Contents/PlugIns/NamedSnapshots.rhp “Snapshots” 8.23.25251.1002

/Applications/Rhino 8.app/Contents/Frameworks/RhCore.framework/Resources/ManagedPlugIns/RDK_EtoUI.rhp “RDK_EtoUI” 8.23.25251.13002

/Applications/Rhino 8.app/Contents/Frameworks/RhCore.framework/Resources/ManagedPlugIns/MeshCommands.rhp “MeshCommands” 8.23.25251.13002

/Applications/Rhino 8.app/Contents/Frameworks/RhCore.framework/Resources/ManagedPlugIns/RhinoRenderCycles.rhp “Rhino Render” 8.23.25251.13002

/Applications/Rhino 8.app/Contents/Frameworks/RhCore.framework/Resources/ManagedPlugIns/RhinoCycles.rhp “RhinoCycles” 8.23.25251.13002

/Applications/Rhino 8.app/Contents/PlugIns/AnimationTools.rhp “AnimationTools” 8.23.25251.1002

/Applications/Rhino 8.app/Contents/PlugIns/SectionTools.rhp “SectionTools” 8.23.25251.1002

/Applications/Rhino 8.app/Contents/PlugIns/RhinoRender.rhp “Legacy Rhino Render” 8.23.25251.1002

/Applications/Rhino 8.app/Contents/PlugIns/Displacement.rhp “Displacement” 8.23.25251.1002

/Applications/Rhino 8.app/Contents/PlugIns/PanelingTools.rhp “PanelingTools” 8.23.25251.1002

/Applications/Rhino 8.app/Contents/Frameworks/RhCore.framework/Resources/ManagedPlugIns/RhinoDLR_Python.rhp “IronPython” 8.23.25251.13002

/Applications/Rhino 8.app/Contents/Frameworks/RhCore.framework/Resources/ManagedPlugIns/GrasshopperPlugin.rhp “Grasshopper” 8.23.25251.13002

/Applications/Rhino 8.app/Contents/Frameworks/RhCore.framework/Resources/ManagedPlugIns/RhinoCodePlugin.rhp “RhinoCodePlugin” 8.23.25251.13002

5

I’ve created this ticket here → https://mcneel.myjetbrains.com/youtrack/issue/RH-89763/RAM-Usage-increases-even-when-Idle

Do you have any other info that may help. Has this always been an issue or only recently?

1 Like
6

Nothing unusual is jumping out from the SystemInfo. I would venture to guess this is related to the 3dm file that you are working with. Would it be possible to share this file with McNeel developers so we can try and reproduce the behavior?

7

Thanks for responding.

This behavior started about two weeks ago. I’ve been using Rhino 8 on Mac for two years, often under much heavier loads, and I’ve never experienced any RAM issues before.

The only change in my workflow is that I recently started using Physically Based materials with an HDRI environment instead of Auxpecker (no textures, just some glossiness, etc.). However, I’m only using the Rendered view, not Cycles. I can’t imagine this alone could cause such a memory increase - could it?

Please see below, three opened Rhino files (each cca 80 MB) generated 65 GB !!!
From this point it appeared several times during week.

Thank You
Ondrej

test2
test21075×922 129 KB

8

Do you have those materials in a file you can share with us? We’re finding it hard to reproduce this.