Matlab functions and parallel_invoke

Question

In my project I have a lot of MATLAB functions. For each function I call Initialize function, when the application starts. I tried to call this functions using parallel_invoke. I tried it several times and allways it takes more time, that code without this. Can somebody explain this ? Is there is something specific in MATLAB or Initialize functions ?

Answer 1

The Matlab Runtime only has a single interpreter thread, so calling Matlab functions in parallel does not gain you anything: when the first function A is called, the MCR acquires a lock and only releases it when that function exits. Calling another function B during that period results in trying to acquire the lock, which then obviously just blocks until A finishes. The reason you see it taking up more time is probably due to the overhead of the locking/parallel_invoke.

I'm not sure what you mean with for each function I call Initialize function: unless you are using multiple Matlab dlls (which will afaik be less performant than having a single dll) you only need to call it's Initalize/Terminate once.