Compiler performance tests on FreeBSD 10.0-CURRENT

Hi all,

By request, I performed a series of kernel performance tests on FreeBSD
10.0-CURRENT, particularly comparing the runtime performance of GENERIC
kernels compiled by gcc 4.2.1 and by clang 3.2.

The attached text file[1] contains more information about the tests,
some semi-cooked performance data, and my conclusions.  Any errors and
omissions are also my fault, so if you notice them, please let me know.

The executive summary: GENERIC kernels compiled with clang 3.2 are
slightly faster than those compiled by gcc 4.2.1, though the difference
will not very noticeable in practice.

Last but not least, thanks to Gavin Atkinson for providing the required
hardware.

-Dimitry

[1]: Also available at:
<http://www.andric.com/freebsd/perftest/perftest-kernel-2012-09-14a.txt>