I cannot set Number of workers as number of cores of my computer

I am using Matlab2014a. I typed

parpool('local',4)

My PC is i7 with 4 cores. But matlab only allows the number of workers at max 2. The message is:

You requested a minimum of 4 workers, but the cluster "local" has the
NumWorkers property set to allow a maximum of 2 workers. To run a
communicating job on more workers than this (up to a maximum of 512 for the
Local cluster), increase the value of the NumWorkers property for the
cluster. The default value of NumWorkers for a Local cluster is the number of
cores on the local machine.

What should I do?

Answer 1

[Titus Edelhofer]

Hi,

you probably have a dual core with hyperthreading? In this case it's a good decision of MATLAB to allow only two workers.

If you think you would really want to start 4 workers: go to the parallel preferences->Manage profiles. Go to the local configuration and change the upper limit to 4.

Titus