Original post is here: eklausmeier.goip.de
In Phoronix Forum I have received feedback regarding the CPU time issue, as described below, see "CPU Usage Time Is Dependant on Load". Right now I use
3.2.0-38-generic #61-Ubuntu SMP Tue Feb 19 12:18:21 UTC 2013 x86_64 x86_64 x86_64 GNU/Linux
So maybe this behaviour is kernel dependant. Therefore I compiled the latest stable Linux kernel, see The Linux Kernel Archives.
make menuconfig
time make
. . .
real 69m59.311s
user 63m38.191s
sys 9m23.687s
It takes more than a complete hour on an AMD FX(tm)-8120 Eight-Core Processor, although basically only one core is used!