Use fastest mirror for downloads - yum-fastestmirror

Fedora uses a worldwide system of mirror servers to distribute packages. When a Fedora system needs package info, packages, or updates, it will by default request a mirror list from a Fedora server. This list is generated based on the repository and architecture requested as well as the IP address of the requesting system and help locate the geographically closest mirrors. This “geographically closest” mirror is supposed to give you the fastest connection - which unfortunately is usually not the case.

The yum-fastestmirror package provides a Yum plugin which measures the speed of available mirrors and sorts the list so that priority is given to the fastest mirrors; this can result in faster yum operations and reduced network congestion -- and with no additional manual effort beyond installing the plugin.

Installing from the command line: # yum install yum-fastestmirror

One may exclude certain domains from even being listed at all by adding the following line to /etc/yum/pluginconf.d/fastestmirror.conf:
exclude=.tw, .jp