Matlab 2019b constantly accessing disk drive

Hi,

I have enountered an issue with Matlab 2019 (A and B) on my Windows 10 laptop.

The computer works fine when Matlab is closed.

However, when Matlab is open, everything slows down and the response to keyboard/mouse input becomes sluggish on all applications (notepad, word, excel, etc.)

If all applications are closed, except for Matlab, Task Manager shows constant disk access.

When Matlab is shut down, the computer resumes normal operation without any issue.

This appears to be related to the use of Matlab software when the application is open.

I am an active Matlab user and have not experienced this before.

Has anyone else encountered this issue?

Is there a solution to this problem?

Anything to do with windows updates (my laptop is up to date) ?

Thanks

[Kashif Rashid]

I installed ML 2020B and have observed the same behaviour.

Has anyone else encountered this slow-down issue?

[Rupchand Sutradhar]

Same problem for R2021a.

Answer 1

[Sunand Agarwal]

Hi

Please try the following workarounds and see if any of them help resolve the issue:

Workaround 1:

Click "Preferences" in the Home tab of the MATLAB Desktop and then go to MATLAB -> General -> Source Control and select "None" and Click "OK". Please restart MATLAB and see if the issue still persists.

Workaround 2:

Does MATLAB open when you try to open it? Can you run any commands in MATLAB Command Window? If so, please try the following command in MATLAB Command Window and then restart MATLAB and see if it is still slow:

>> opengl('save','software')

Workaround 3:

If that doesn't work, could you please try the following steps and see if your MATLAB is still slow?

Please try (a) regenerating preferences, (b) restoring MATLAB to default paths and (c) rehashing toolboxcache:

a) How do I regenerate my MATLAB preferences?

https://www.mathworks.com/matlabcentral/answers/99625-how-do-i-regenerate-my-matlab-preferences

b) Restore search path to factory-installed state.

Before modifying the search path, you can take a backup of your 'pathdef.m' file, which can be located by using the command in MATLAB Command Window

>> which -all pathdef

Before proceeding, you should backup this file by copying it to a folder outside of your MATLAB path. After making the backup, please execute the following commands in the MATLAB Command Window to restore the default MATLAB search path.

>> restoredefaultpath

c) In MATLAB Command Window, execute the following command:

>> rehash toolboxcache

For more information about the above command, please take a look at the following link:

https://www.mathworks.com/help/matlab/ref/rehash.html

d) After the above steps, please use MATLAB normally to see if the issue occurs again. If the issue is resolved, then you can save the new MATLAB search path by executing the following command:

>> savepath

Hope this helps.

[Kashif Rashid]

Hi,

I just tried all of the workarounds and none worked.

Also, I recently uninstalled and re-installed Matlab 2020B - so all the options are as given by default.

The performance issue is clearly evident when Matlab is open and disappears when it is shut-down.

The benchmark (bench) test shows that computer slows down to a ridiculous level:

tic; bench; toc gives:

>> Elapsed time is 25.829021 seconds.

I am using a Windows 10, Intel Xeon 2176M CPU @ 2.70 GHz with 32 GB ram and a Nvidia Quatro P2000 gpu.

Rgds, Kashif

[Kashif Rashid]

For interest, I have now resolved this issue.

The issue (though evident with Matlab open) was not due to the application, but rather my Dell 5530 laptop.

It appears that there is a known issue with poor thermal CPU control on the laptop. After making suitable DELL driver updates, the laptop is now functioning properly.

The bench test in Matlab is completed in 3.7 seconds.

Thanks.