Matlab and Linux - problems with MCR process

I have reinstalled Debian Testing (upgraded from Bookworm) and I installed Matlab 2024a on it.

Now when I launch Matlab, MCR process (MCR 0 interpret) kicks off. It takes 5% CPU usage and Matlab command line is blocked - I cannot execute any command until I forcefully kill MCR process. Then I can use Matlab's interpreter again.

The funny thing is that in my previous installation of Debian Testing (also based on bookworm) with Matlab 2023a this issue didn't appear.Now when I test older versions of Matlab (2023, 2021) the same thing happens.

[Umar]

Hi Marbor,

The MCR process is essential for running compiled MATLAB applications and scripts, but in your case, it seems to be causing a bottleneck. One possible explanation could be compatibility issues between the newer version of MATLAB and the Debian Testing environment, leading to inefficient resource management. To troubleshoot this issue, you can try the following steps: 1. Check for any updates or patches for MATLAB 2024a that address compatibility issues with Debian Testing. 2. Monitor system resource usage using tools like top or htop to identify any abnormal behavior or bottlenecks caused by the MCR process. 3. Consider reinstalling MATLAB 2024a or reverting to a previous version that worked without issues, such as MATLAB 2023a. 4. Look for community forums or support resources specific to MATLAB and Debian Testing for insights from other users who may have encountered similar problems.

[Piyush Kumar]

@marbor, Did you check the MATLAB R2024a System Requirements for Linux page?

[August Johansson]

@marbor I have the same problem with debian testing and recent matlab releases (I've tested 2022a up to 2024b prerelease). It seems to works fine with nojvm, but with java it's incredible slow.

With only nodesktop:

$ matlab -nodesktop

MATLAB is selecting SOFTWARE rendering.

< M A T L A B (R) >

Copyright 1984-2024 The MathWorks, Inc.

R2024b Prerelease Update 2 (24.2.0.2651190) 64-bit (glnxa64)

June 21, 2024

To get started, type doc.

For product information, visit www.mathworks.com.

Prerelease License -- for engineering feedback and testing

purposes only. Not for sale.

>> tic, ls, toc

Downloads Projects Software tmp

Elapsed time is 104.853687 seconds.

>>

WIth nojvm:

$ matlab -nojvm

MATLAB is selecting SOFTWARE rendering.

< M A T L A B (R) >

Copyright 1984-2024 The MathWorks, Inc.

R2024b Prerelease Update 2 (24.2.0.2651190) 64-bit (glnxa64)

June 21, 2024

For online documentation, see https://www.mathworks.com/support

For product information, visit www.mathworks.com.

Prerelease License -- for engineering feedback and testing

purposes only. Not for sale.

>> tic, ls, toc

Downloads Projects Software tmp

Elapsed time is 0.043780 seconds.

>>

Due to the difference with and without java, I also tested changing java version to OpenJDK, but to no avail:

>> version -java

ans =

'Java 17.0.12+7-Debian-1 with Debian OpenJDK 64-Bit Server VM mixed mode, sharing'

>>

>> tic, ls, toc

Downloads Projects Software tmp

Elapsed time is 106.418971 seconds.

Did you find a solution?

EDIT:

Setting the nofile limit solved it. This is described https://se.mathworks.com/matlabcentral/answers/2127081-library-initialization-failed-unable-to-allocate-file-descriptor-table-out-of-memory-matlab-is

I.e.

echo > /etc/security/limits.d/systemd.conf "* hard nofile 65536"

[marbor]

Hi August,

Thank you for your solution. I can confirm it works.

BTW. Since I moved from windows to Debian about ten years ago I installed Matlab at least dozen or so times, and... I have _literally_never_ experienced it working out-of-the-box! There was always something you needed to fix, circumvent or patch and even after customization it still didn't work as flawlessly as in Windows.. For example, I've never succeeded to enable drag'n'drop m-file from Dolphin (KDE's file manager) into Matlab editor. Java-related problems, opengl and graphic card problems - they were present 10 years ago and they are still present.

Currently, I'm going to test matlab inside docker approach. I hope it will be a better, more stable approach than searching for new solutions to old problems after each installation.

[Umar]

Hi @Marbor,

As I mentioned in my posted comments section, “ To troubleshoot this issue, you can try the following steps: 1. Check for any updates or patches for MATLAB 2024a that address compatibility issues with Debian Testing. 2. Monitor system resource usage using tools like top or htop to identify any abnormal behavior or bottlenecks caused by the MCR process. 3. Consider reinstalling MATLAB 2024a or reverting to a previous version that worked without issues, such as MATLAB 2023a. 4. Look for community forums or support resources specific to MATLAB and Debian Testing for insights from other users who may have encountered similar problems.” Glad to know your problem is resolved. Please let us know if you still have any further questions.