# yum clean all
Loaded plugins: fastestmirror, presto, refresh-packagekit
Cleaning repos: InstallMedia adobe-linux-i386 fedora google-chrome livna opennms-stable-common
              : opennms-stable-fc13 openwebmail rpmfusion-free rpmfusion-free-updates
              : rpmfusion-nonfree rpmfusion-nonfree-updates updates virtualbox
Cleaning up Everything
Cleaning up list of fastest mirrors
0 delta-package files removed, by presto

# yum makecache
Loaded plugins: fastestmirror, presto, refresh-packagekit
Determining fastest mirrors
fedora/metalink                                                              | 9.0 kB     00:00
updates/metalink                                                             | 7.7 kB     00:00
 * fedora: ftp.cs.pu.edu.tw
 * livna: rpm.livna.org
 * rpmfusion-free: mirrors.163.com
 * rpmfusion-free-updates: mirrors.163.com
 * rpmfusion-nonfree: mirrors.163.com
 * rpmfusion-nonfree-updates: mirrors.163.com
 * updates: ftp.cs.pu.edu.tw
adobe-linux-i386                                                             |  951 B     00:00
adobe-linux-i386/filelists                                                   | 140 kB     00:02
adobe-linux-i386/primary            
..
..
# yum update
..