Creating a swap file for tiny cloud servers

A few months ago while setting up a few cloud servers to host one of my applications. I started running into an interesting issue while building Docker containers. During the docker build execution my servers ran out of memory causing the Docker build to fail. The servers in question only have about 512MB of RAM and the Docker execution was using the majority of the available memory. My solution to this problem was simple, add a swap file.

Sar & Sysstat: Linux Performance Statistics with Ease

Whenever I perform any type of activity that requires me to look at historical system statistics such as load average, CPU utilization, I/O wait state, or even memory usage; I usually skip the System Monitoring Applications like Nagios or Zenoss and start running the sar command. While I'm not saying that sar completely replaces those tools, I am saying that sar is quick and dirty and if all you want is some raw numbers from a certain time frame; sar is a great tool.