how to throttle CPU usage for fitrgp?

(I hate asking something this trivial, but I'm frustrated... thanks for reading.)

My gaussian process regression via fitrgp automatically uses the maximum number of physical cores.

maxNumCompThreads(1)
mdl = fitrgp(X_train, Y_train,'KernelFunction', 'squaredexponential');

Specifically, setting the maxNumCompThreads is not effective in limiting CPU usage.

What am i missing here for throttling built-ins? I want to hard-limit it to may maybe 20 or 30 cores on this shared memory system.

Answer 1

[jessupj]

(SOLVED)

So... for whatever reason, restarting matlab got maxNumCompThreads to start managing usage. (Same system environment, same workspace definitions). I think the explanation/answer here is 'something broke internally; restart the matlab kernel to fix it' unless there's a better answer that doesn't require that.

[Drew]

On what platform & CPU configuration did you observe reaching a state where maxNumCompThreads is not managing max thread usage? Please file a support case with reproduction steps if the condition is repeatable.

Answer 2

[Drew]

Use maxNumCompThreads https://www.mathworks.com/help/matlab/ref/maxnumcompthreads.html to set the desired max number of computational threads.

LASTN = maxNumCompThreads(N)

If this answer helps you, please remember to accept the answer.

[Walter Roberson]

? they are already doing that, but it isn't helping.

[jessupj]

maxNumCompThreads is ignored. the code snippet, when i run it, uses O(100) cores even despite the instruction maxNumCompThreads(k) for whatever value of k I throw at it