Why isn't my entire processor being used/utilized when I execute a script file?

Hi,

I'm not quite sure this problem pertains directly to MATLAB, but here it goes:

I have the Parallel Computing Toolbox and executed "matlabpool open." It has recognized the 4 physical cores of my i7. To monitor my CPU usage, I use a gadget on my desktop. When I execute a script file, I would expect all of my cores to ramp up to %100 usage. However, it doesn't. They all hover around 25%, as opposed to one core sitting around 30-35% prior to the PC toolbox. How come my processor is not being used to it's entirety?

Other info if needed:

MATLAB R2011a

Sony VAIO F-Series

i7-2670QM 2.20GHz

8GB Ram

nVidia GeForce GT540M

Battery settings are set to generic "High Performance" mode and the laptop is plugged in.

If any other info from my side could be of help, let me know.

Thanks,

Sam

Answer 1

[Jason Ross]

Are you using functions from the Parallel Computing Toolbox like parfor, spmd, jobs/tasks, batch, etc?

Is your code doing something that's not processor-intensive (like reading in a large file)

How much RAM is utilized? If you have exhausted the RAM and are relying upon much slower disk access, the CPU will not be fully utilized.

Answer 2

[Samuel]

At this point in time, I'm only using 60-80% of my ram, if that much. Most of the script file is just plotting figures and writing them to .png files (42 of them at 1200 dpi). There are anywhere from 2.5 to 7.5 million data points (strain data recorded at over 600Hz for 1 to 4 hours). And unfortunately, no Parallel code at the moment. I'm pretty sure there is a way to use parfor, but I'm still learning a lot of the basics.

[Jason Ross]

You might want to take a look at using batch first, it might do exactly what you want.

http://www.mathworks.com/help/toolbox/distcomp/batch.html