MATLAB / Simulink runs slower in batch mode than interactively (Windows)

We have hundreds of Requirements (SLREQX), models (SLX, SLDD) and Test Manager files (MLDATX) and traceability between them (SLMX) and a script which are meant to scan our entire repository and perform reasonablenss checks & collect metrics about these files.

While debugging these MATLAB scripts, I experience a typical runtime of 10 minutes on a Windows Server 2019 host (details below). This duration was measured using 'tic' and 'toc' in the script.

In "production" I want the script to run headlessly via a Continuous Integration (CI) agent on the same host PC, but in this mode the script takes more than 1 hour (60 minutes). It is expected that the same tasks take significantly longer (more than 5x) in headless / batch mode? What else should I investigate to enable a run-time similar to interactive / graphical mode?

The CI agent runs as a functional/service account, but I have confirmed this account's MATLAB preferences are identical to mine (such as the Java Heap Memory preferences - set to 8 GB).

On the CI agent, the script is launched via the following method (Windows batch script):

$MATLAB2021ROOT\matlab.exe -wait -noFigureWindows -sd "$WORKSPACE" -batch "$SCRIPT_COMMAND; quit force;"

Where SCRIPT_COMMAND is (paraphrasing)

• open Simulink Project
• change directory & add additonal folder to MATLAB path
• run reasonablenss checks & collect metrics <- this is the part that is taking the longest, but is 10 minutes in graphical mode

Host PC details

• MATLAB 2021 Update 4
• Xeon processor @ 3GHz, 96 cores (2 physical CPUs)
• 192GB RAM, NVME storage
• Windows Server 2019

Thank you

[Yongjian Feng]

Hi Nathan,

This could be caused by different setup/configuration of the Host PC. To compare apple to apple, it makes sense to try the same script headless on the developement machine. This will be a better comparison.

Thanks,

[Yonnatan Bar]

Same issue here ,

When launching Matlab and running and generating a code from the APP , it takes 20-25 minutes.

When trying the same on the same computer using headless through CMD , 2 Hours .

Same branch , same pc , same apple.

[Guillaume]

Same issue here,

My Simulink Test Manager runs in 35 minutes in interactive mode but when triggered by my GitHub Action it takes 5 hours !!! On the same machine obviously, which is also a Windows Server 2019...

[Nathan]

@Yongjian Feng - I have done as suggested and executed the same script headlessly on the development machine in question (i.e. executed the same Windows Batch script that Jenkins CI would have executed). I still observe that the task completes very quickly compared to when CI does the same task: 13 minutes vs more than 90 minutes.

I am beginning to wonder if the functional account that performs the Jenkins CI tasks may be somehow configured differently that my personal account which I am using for testing. Although I am not sure where to begin my investigation ...

[Michael]

i have the same issue, did you find any solution?

[Nathan B]

@Michael - still no solution, still dealing with very slow MATLAB /Simulink jobs in our CI environment

Open to ideas if you have any ...

[Michael]

@Nathan B please see my comment here

Answer 1

[Michael]

I made some progress.

My setup is as following:

• Linux RHEL9 hosting Jenkins as a Container (run by Podman)
• Windows 2022 Server as a Jenkins Agent with MATLAB 2024b Installation

For executing MATLAB commands I use the MATLAB Plugin for Jenkins (https://plugins.jenkins.io/matlab/), but I built a Wrapper function to redirect all temporary directories to the job's workspace, because otherwise MATLAB might hang if there are multiple jobs running at the same time.

After check-out from our VCS, a simple Script collects all tests from all the models into a test suite and then runs them. This takes about 5 to 6 minutes on my local machine, and about 30 min when done via the Jenkins Job on the agent.

What I found out with ProcMon is that even on the remote Agent the script exuction actually only takes 5-6 min but MATLAB keeps running and performing unidentified background work for 25 min before eventually closing. I could not stop MATLAB with any MATLAB command like bdclose all, exit or quit.

What I found to resolve the issue is to NOT cleanup the workspace, specifically the "cache" folder generated by Simulink. What I do instead is to leave the workspace as is and only update any out-of-date files which are under source control. When the cache is not deleted, the Pipeline takes as long as the local run (5-6 min).

We use this workaround for CI builds, but cannot use it for Release builds. So it is not really a solution for us, but what can you do.

I am honestly quite frustrated about MATLAB's intransparent background tasks.

We also needed quite some time to figure out that MATLAB shares sldd-Caches between Instances. If you do not redirect the temporary directories by changing environment variables, MATLAB instances just hang because the read/write on those Caches lead to a deadlock. In my opinion the MATLAB Plugin for Jenkins should provide a solution for this out-of-the-box, since running multiple Jobs concurrently is a common theme in Continuous Integration.