MATLAB 2018b freezes with >100% CPU usage on Mac OS Mojave 10.14.3

Hello,

I run MATLAB r2018b on a MacBook Pro 2018 with 16 GB of RAM and a 2.7 GHz i7.

Every time I use MATLAB, after ~5,10 min of normal usage (basic tasks like plots or small vector computations), the CPU usage goes above 100% and the software becomes unusable, with an average of ~1.3 GB or RAM used. In this condition, I cannot save variables or plots and I have to force the termination of the session, but without seeing any error message.

After reading other MATLAB Answers, I can say that don't use Magnet and I disabled the Source Control and the auto-refresh of the Current Folder. The Java Heap Memory is set to a maximum of 4 GB. This issue occurs regardless if I am connected with Internet or not. Re-installing from scractch didn't solve the problem.

What could be the issue? The software alsways crashes after a short usage, I never experienced such problems with the r2016 version.

Thank you very much for your help.

[Ken Atwell]

The next time this happens:

1. Open the Activity Monitor App.
2. Choose "MATLAB" from the Process Name column.
3. Click the Gear and "Sample Process". Wait for it to finish (seconds to upwards of a minute)
4. Save the sample as a text file
5. Upload this file to this MATLAB Answers topic as an attachment.

[Francesco Carotenuto]

Hello Ken,

thanks for your answer.

I sampled the process, it is attached.

[Ken Atwell]

I took a long look and, sorry, nothing is jumping out at me. I would describe your problem to support, including the file you've uploaded here.

[Francesco Carotenuto]

Thank you very much for looking at this. I will ask to support.

[Gernot Fattinger]

Has this been solved? I have the exaxt same issue.

[Francesco Carotenuto]

Not yet unfortunately. From the support they suggested to regenerate my preferences in the

/Users/{username}/Library/ApplicationSupport/MathWorks/MATLAB/R2018b folder, but it didn;t work.

This is still happening after updating to R2019a, but I noticed that it mostly happens when I try to save objects, like new variables or plots. If I don't try to save anything in my working folder, MATLAB usually works fine, but when I try to save, the object is not saved and my CPU usage rises up to 100~120% and the software becomes unusable.

[Ayman Suliman]

I'm getting the same issue, it just recently started happening a few hours after updating my Mac to 10.14.5 .

I noticed the virtual memory keeps increasing while it is frozen, so I suspect it's some kind of memory leak? The virtual memory size (from the activity monitor) went over 90 GB before I terminated it.

I'm on 2018b.

EDIT: Reinstalling has solved the problem for me (for now).

Answer 1

[hb chen]

Now, I have solve this problem. There isn't Magnet app installed in my Mac. But there is another window snapping apps in my Mac: Eudi，so I closed it and open Matlab again, it works!

Hope this can help you!

Answer 2

[Cao Duo]

https://www.mathworks.com/matlabcentral/answers/421446-r2018b-r2019a-runs-very-slow-on-macos-10-14?s_tid=answers_rc1-2_p2_BOTH

This article helps! I had the same problem but turn off the Magnet helps me!

Answer 3

[Eric]

Same here. No Magnet App. R2019 on MacOSx 10.14.5 on MacbookPro 2018 15". Hangs for several minutes, UI unresponsive on any window. Activity Monitor MATLAB process sample attached.

/eric rehm

Takuvik / ULaval

Answer 4

[Deepak Ingole]

The same issue persists with macOS Catalina (10.15) and MATLAB2019a. The solutions given at https://www.mathworks.com/matlabcentral/answers/421446-r2018b-r2019a-runs-very-slow-on-macos-10-14?s_tid=answers_rc1-2_p2_BOTH doesn't help. This is happening after macOS update, MATLAB freezes for some time and then works well. Need help to solve this issue.

Thank you.

[Ayman Suliman]

Does it happen when you run Simulink? I noticed the problem occurred for me when using the "Scope" tool in Simulink, but that was a long time ago. Normal Matlab works fine for me.

[Deepak Ingole]

No, I am not using Simulink. For me, it freezes after plotting some figures.

Answer 5

[hb chen]

！！The same issue persists with macOS Catalina (10.15) and MATLAB2019a/MATLAB2019b. Once I open a .m file and run it. Matlab freezes and the CPU usage goes above 100%.

Please help! Thanks!

[hb chen]

My computer is macbook pro 2019.