Swappiness

From LinodeWiki

The performance of Linux 2.6's virtual memory subsystem (VM) can be tuned in a number of ways. One of the most important is swappiness, which controls the degree to which the kernel prefers to swap when it tries to free memory. This value defaults to 60, and since Linodes have I/O limiting, the swap traffic can eat up your I/O tokens. You can adjust swappiness by doing the following as root:

   sysctl -w vm.swappiness=25

If your distribution does not have a sysctl command:

   echo 25 > /proc/sys/vm/swappiness

You should try different values to see what best suits your applications, but anecdotal evidence suggests that 25 is a good value to start with on a Linode.

If your distribution has the sysctl command, then you may be able to add the vm.swappiness to /etc/sysctl.conf to set the value at boot.