Fusion 360 240% CPU load on Macbook Pro 16" OS big sur

[Anonymous]

Hi all,

recently, I encounter very high CPU load while having Fusion 360 opened (and not doing anything). When I was using Fusion a couple of months ago (on the same machine) I didn't encounter the issue. I already have tried some of the advices from other posts but nothing seemed to work =(

Attached you can find an image of the activity monitor.

Is there something else I can try besides uninstalling the 3d mouse or using fusion in offline mode?

Thanks in advance,

sebastian

[darran]

Did you manage to solve the problem and/or find a workaround?

I updated my MBP 16" to Big Sur earlier this week. I just sat down to do some Fusion 360 work and ... the fans are on full and Fusion is using around 100% of cpu. That's with a blank project. If I do something simple like create a rectangular profile and try to extrude it, cpu usage goes up to 170-190%.

[darran · Accepted solution]

Hey Sebastian. Interesting that you mention the 3D mouse. This turned out to be the cause of my Fusion issue. Even with the 3D mouse turned off, just having the driver installed was enough to cause the excessive CPU usage. I fully removed the driver and the issue went away. I then installed the 3D Connexion beta driver (for Big Sur) and again have Fusion working normally with the input device I really enjoy. 

[Anonymous · Accepted solution]

Hi Daran,

The problem still occurred when starting Fusion, even after I had erased the 3D connexion driver. However, I tried and installed the macOS Big Sur beta driver and the issue was gone 😃

So, maybe I didn't remove the 'old' driver completely or something but now it works!

Thanks and best regards,

Sebastian

[darran]

For anyone else reading this using both the 3D Connexions SpaceMouse *and* the CADMouse, this beta driver will prevent your mouse from responding to clicks. You'll be able to move the mouse cursor but clicks will have no effect, not just in Fusion but for everything. If this happens, you'll need to update the mouse firmware by following the instructions on https://3dconnexion.com/uk/support/faq/cadmouse-doesnt-click-on-macos-11-0-big-sur/. Note, even once you upgrade the firmware, you'll have to connect via Bluetooth rather than the Dongle ... at least for now.

[daanbrinkmann]

So I'm encountering the same issue for (spacenavigator product). I uninstalled 3dconnexion drivers, clean install of fusion, upgraded OS and issue still persists!