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I'm compiling OpenCV on an AM335x 1GHz ARM® Cortex-A8 (BeagleBone Black's processor). RAM is limited too (512MB DDR3). Is there a point in specifying more than one job, i.e., make -j4, like the installation script does?

Spyros Maniatopoulos
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    Read this: http://stackoverflow.com/questions/15289250/make-j4-or-j8/15295032#15295032 – MadScientist Jan 20 '16 at 06:11
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    Probably `-j4` is too much. But you might win with `-j2`. It depends on other factors of your system and also what the recipes in your makefile is actually doing. Only experimentation will tell. – MadScientist Jan 20 '16 at 06:12

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It can be. Many commands executed by make are I/O bound. If you have only one job, it can often be blocked awaiting I/O. If you have multiple jobs, when one job is blocked awaiting I/O, another might be able to use the CPU, and vice versa. That gives more utilisation of the CPU and I/O system, and thus faster building.

Raedwald
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