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Subject: Re: GSOC 2013 project " Kernel Size Reduction for Embedded System "
From: Adrian Chadd <adrian@freebsd.org>
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Cc: Wojciech Puchar <wojtek@wojtek.tensor.gdynia.pl>,
 Alfred Perlstein <bright@mu.org>,
 FreeBSD Hackers <freebsd-hackers@freebsd.org>, Amit Rawat <aamitr4@gmail.com>
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On 9 April 2013 11:47, Edward Tomasz Napiera=C5=82a <trasz@freebsd.org> wro=
te:
> In order to optimize - in this case for size - we need a way to measure
> what should we focus on, and it looks like we don't have it yet.

We have a good starting point. We can look at the code/data/bss from
each .o file that's included in the build.

You can build a bare-bones kernel and modules, and use that to see how
big things are.

You can group those by subsystem to get an idea of how big each
subsystem is. Whether or not it's loaded is (mostly) irrelevant - if
we compile out USB but then include it as a module, the underlying
size is almost the same anyway.

Thanks,



Adrian