What are Controlling and Computing Processes?

Question

My wolfram user portal claims that I have 2 controlling processes and 8 computing processes.

Mousing over the question mark gives me some information, but I still don't fully understand what this means.

• Does 2 Controlling Processes mean I can install Mathematica on 2 different computers?
• If not, what are they and how do I make use of them?
• Are Computing Processes like the number of cores I can use simultaneously? (Does Mathematica even support multicore?)
• If so, how can I make use of this?

Answer 1

1. Computing Processes are the number of main kernels you can use at the same time. Therefore, you can have on the same computer two Mathematica sessions running and while one computation is running, you can use the other one to do something else. It has nothing to do with your license which is valid for only one computer.

2. The probably easiest method if you want to use 2 sessions of the same Mathematica version is to create a new Kernel Configuration (Evaluateion -> Kernel Configuration Options) and use your default local kernel in one notebook and the new other kernel in the other notebook. Or, which depends on the operating system, you start a new Mathematica. In Linux, I simply click on the Mathematica starter which indeed opens a new Mathematica instance. On MacOSX I could start it from terminal or make a second copy of the whole package. In Windows there is surely a way too.

3. Yes. I you run ParallelTable for instance, you get 8 sub-kernels which do the parallel work.

4. Just use one of the parallel function you find here

Answer 2

The 2 CONTROLLING processes effectively means you can run 2 front-ends at the same time. This might be, say, Mathematica 8 and Mathematica 9 on the same machine at the same time, or one copy of Mma 9 on your desktop and another on your laptop (if your License allows same: check with Wolfram).

The COMPUTING processes (8) are the number of slaves / cores you can run, as you suggest. This used to be 4 under a standard license under v8, but seems to have risen to 8 processes under v9 ... which is most welcome :)

You can find formal definitions of the terms here:

http://www.wolfram.com/legal/agreements/wolfram-mathematica.html