Farkas, Don't email just to me offlist. Keep this onlist.
How much of this is network access and how much is disk? B/c I doubt very much that you're cpu bound at all.
everything is on the local mirror server which is on a gigabit lan. is there any way to banchmark mock and different part of it?
in the mock config you're using (/etc/mock/.....) look for:
config_opts['yum.conf'] = """ [main] cachedir=/var/cache/yum debuglevel=1 reposdir=/dev/null logfile=/var/log/yum.log retries=20 obsoletes=1 gpgcheck=0 assumeyes=1
and change debuglevel=1 to debuglevel=3
and then look at the root.log and look for lines that contain:
"time:"
that will tell you how long is being spent in each section
post those times. -sv