How to “nice” the I/O

• ionice : http://linux.die.net/man/1/ionice|ionice
• Install

aptitude install util-linux

• Extreme case : only run a program when I/O is idle (root mandatory) :

ionice -c3 xfs_fsr -t 600

• An addition to my .bashrc to ensure my niced program also preserve my I/O

alias nice='ionice -c2 -n7 nice'

• My source : http://gentoo-wiki.com/HOWTO_Light_Gentoo_Installation#Extra:_ionice