The Matlab 2017a has a restriction on the number of "workers"?

In earlier versions of MATLAB there was a restriction on the number of 'workers' - there was a maximum of 12, but this was lifted as of 2015a. As I am using 2017a, I should not be experiencing this. I have checked my 'numcores', here is the result.

>> feature('numcores')

MATLAB detected: 16 physical cores.

MATLAB detected: 16 logical cores.

MATLAB was assigned: 16 logical cores by the OS.

MATLAB is using: 16 logical cores.

but when I run my program, Matlab shows

Starting parallel pool (parpool) using the 'local' profile ...

connected to 12 workers.

[liu lin]

the number of workers which can work is equal to the number of the gpu of your computer. when you start parallel compute really, the color of the blue bar would change to green.

[Chosen Zhou]

I know this, but in fact I have 16 cores, but Matlab only use 12 cores to run my program. I want to figure out whether 12 cores is max in Matlab, or whether it is my computer's setting problem.

Answer 1

[Steven Lord]

Open up the parallel preferences. What is the preferred number of workers in a parallel pool listed in the preferences?

Also open the Cluster Profile Manager using the link on the preferences window and check the NumWorkers property to ensure it has not been set explicitly to open 12 workers.

[Chosen Zhou]

Thank you for your answer. It is really helpful.