Simulink Test Iterations Issues when running in Parallel Mode

CONTEXT:

I'm running some Simulink Test harnesses programmatically for control engineering purposes. First, each test use the pre-load call back to load variables and set cache folder to manage simulation artifact. Then it run each set of test either in parallel or in serials.

ACTION:

I tried to add parameter iterations to 1 test in the group.(See #1) It run well in the simulink test manager GUI sequentially. it ran well sequentially programmatically, but the unexpected happen when I tried to run it parallel.

EXPECTED:

It split all test in group and run in parallel pool without any issues like #3 and and show in test results the iterations #4.

RESULT:

It split all test in group and run in parallel pool but it had a fetch next issue like in #2.

Any idea?

Can simulink test iteration be run in parallel mode?

INFO:

1 . To not have a data concurrency issue per test, I do create 1 artifact cache folder per test using simulink test callbacks . but I didn't do so per iteration, I hope it didn't matter and I was a bit lost on how to.But, I think that could be related. Ref:

https://stackoverflow.com/questions/64824205/how-to-fix-conflicting-simulink-simulation-accelerated-artificats-issue-when-run

https://www.mathworks.com/help/simulink/ug/model-reference-simulation-targets-1.html

2 . Here's some literature I read on the subjects

https://www.mathworks.com/help/sltest/ug/run-multiple-combinations-of-tests-using-iterations.html

https://www.mathworks.com/help/sltest/ref/sltest.testmanager.testcase.additeration.html

3 . I'm using the runInParallel command from the matlab.unittest.TestRunner pluggin. I'm also using matlab.unittest.plugins.DiagnosticsRecordingPlugin.

CODE & LOGS:

#1 Here I try to use Parameter Override and Iterations to split 1 test in 2 iteration. All other test are individual test.

for i = 1:6
    if regexp(requirement{i},'FOO' ,'once')
        for j = 1:2%7
            %% Generate Variant Scenarios
            Foo= TS_Foo(j);
            %% Parameter Set
            currParamName = char(strcat("Parameter Set ",string(j)));
            ps{i,j} = addParameterSet(tcase{i},'Name',currParamName);
            po{i,j} = addParameterOverride(ps{i,j},'A',Foo.A);
            po{i,j} = addParameterOverride(ps{i,j},'B',Foo.B);
            po{i,j} = addParameterOverride(ps{i,j},'C',Foo.C);
            po{i,j} = addParameterOverride(ps{i,j},'D',Foo.D);
            %% Iterations
            % Create test iteration object    
            testItr = sltest.testmanager.TestIteration();
            % Use the parameter set in this iteration
            testItr.setTestParam('ParameterSet', currParamName);
            % Add the iteration object to the test case
            addIteration(tcase{i},testItr,currParamName);
        end

#2 Here I run 6 test with 1 test having 2 iterations in parallel. so it's 7 test total split.

Split tests into 7 groups and running them on 6 workers.
Error using parallel.FevalFuture/fetchNext (line 255)
The function evaluation completed with an error.

Error in
matlab.unittest.internal.TestRunnerExtension/runInParallel>printFinishedOutput
(line 85)
    groupIdx = fetchNext(groups);

Error in matlab.unittest.internal.TestRunnerExtension/runInParallel (line 58)
printFinishedOutput(groups, stream);

Error in runTest (line 141)
results = runInParallel(runner,suite);

Caused by:
    Error using
    matlab.unittest.plugins.testrunprogress.ConciseProgressPlugin/runTestClass
    (line 59)
    In 'MATLAB:unittest:TestRunProgressPlugin:Running', parameter {0} must be
    a scalar.

#3 Here I ran 35 test in parallel with no iterations, without any issue.

I also ran 6 test in parallel, without iteration with no issue.

2021-08-26T18:39:18.9495254Z Split tests into 22 groups and running them on 8 workers.

2021-08-26T19:37:12.5841596Z ans =
2021-08-26T19:37:12.5842363Z 
2021-08-26T19:37:12.5842546Z   35x6 table
2021-08-26T19:37:12.5842637Z 
2021-08-26T19:37:12.6891297Z                                   Name                                  Passed    Failed    Incomplete    Duration      Details   
2021-08-26T19:37:12.6913253Z     ________________________________________________________________    ______    ______    __________    ________    ____________
2021-08-26T19:37:12.6913549Z 
2021-08-26T19:37:12.6919980Z     'API_Test_Files28 > API_Test_Suites/MUT_Harness_****#1'              true      false     false         1824.4      [1x1 struct]
...
...
2021-08-26T19:37:12.6943686Z     'API_Test_Files28 > API_Test_Suites/MUT_Harness_****#35'             true      false     false         323.12      [1x1 struct]

#4 Here I ran the the 6 test plus the iteration in sequential mode.

  7×6 table

                                                Name                                                 Passed    Failed    Incomplete    Duration      Details   
    _____________________________________________________________________________________________    ______    ______    __________    ________    ____________

    'API_Test_Files49 > API_Test_Suites/MUT_Harness_****'                                          true      false     false         1002.2      [1×1 struct]
    'API_Test_Files49 > API_Test_Suites/MUT_Harness_***(TableIteration=ParameterSet1)'    true      false     false          502.1      [1×1 struct]
    'API_Test_Files49 > API_Test_Suites/MUT_Harness_***(TableIteration=ParameterSet2)'    true      false     false          277.4      [1×1 struct]