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Fusion Uses Ludicrous Amounts of RAM on Opening - Mac

Message 1 of 5
210 Views, 4 Replies

Fusion Uses Ludicrous Amounts of RAM on Opening - Mac


I have a problem!

The Problem

I open Fusion from either Spotlight or the dock and it will do either one of two things:

Situation 1:

I click open Fusion, it loads for 1-3 minutes, with the white screen that says fusion, with the first loading screen (cant find screenshot) over it.  and then an apple message says that I am out of system memory and need to force quit applications to save it. Fusion is shown using 42-46GB of RAM and is not responding (attached). Waiting from here does nothing.

Situation 2:

I click to open Fusion, and it stays perpetually loading on the first (?) loading screen (attached). Nothing else happens until I force quit it and get a message to report it to Autodesk.


Today, Situation 2 only happens, but in the 2 days before today, Situation 1 was 90% of my attempts to open Fusion.


I currently run Fusion on a Macbook Air M1 2020 with 8GB LPDDR4 RAM and a 251GB (maybe its 256 but it says 251?) SSD. I am on MacOS Ventura 13.5.1

I am running the student version of Fusion.

I have been running Fusion just fine for the last ~2 years on this exact computer and only now have had a problem, so I don't think that the specs are the issue.

Here's what I have tried:

Reinstalling Fusion

I have done this multiple times. Fusion opens fine for the first time, and I can use it however I want. Once I quit and try to reopen it after, the problem reappears. I could keep doing this, but it is not ideal at all.


This article tells me to put a command into my terminal.

I have tried that and there was no change whatsoever.

Clearing Temp/Cashe

Last thing that Fusion support could find out, but there was no change.

What I could try:

Updating MacOS

I have no idea why I haven't tried it yet, but that is definitely an option

Please help me, I need to be able to use Fusion for my VAIRC team.

Message 2 of 5
in reply to: cooper17814W

I'm still having the problem. Does anyone know how to fix it? Sorry about the bump.
Screenshot 2024-03-29 at 1.11.13 PM.png

Message 3 of 5
in reply to: cooper17814W

Hate to necropost, but it hasn't resolved itself.

Message 4 of 5
in reply to: cooper17814W

not to be that guy but when the system reports that Fusion wants 39 GB and you have 8 GB physical, that is massive amount of swapping going on.  maybe the disk is full or fragmented, and while SSD is fast, it is not a substitute for ram


Apple memory may be expensive, but in todays world, memory is needed.



Message 5 of 5
in reply to: untrustedone

I get that, but for over a year before the issue happened, I was able to use Fusion just fine on this computer. I don't think that an update would add so much RAM demand. I could be wrong though.

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