From: Boris Gjenero <boris.gjenero_at_gmail.com>
Date: Thu, 5 Mar 2009 21:53:15 -0500

Hello,

By default GNU make runs one job at a time. This fails to take
advantage of multiple cores and/or multiple CPUs on the system that's
doing the building. With the -j option one can specify how many jobs
to run at a time. I have a 4-core Intel Q6600 CPU, and -j 4 cuts the
build time in half, from about 10 minutes to about 5 minutes. Rockbox
seems to build correctly; what I got with -j 4 is identical to what I
get without the -j option. The only disadvantage is that output
messages from different jobs can be intermingled.

Here is some info on this GNU make option:
http://www.gnu.org/software/automake/manual/make/Parallel.html

For now I've still been avoiding this option because when working on
other patches or bugs I do not want to have potential problems from
the build process. Is it okay to use the option?

Regards,

Boris
Received on 2009-03-06