Below: A time travelling resource monitoring tool (2021)

"First, cgroups emerged as the de facto way to control and monitor resources on a Linux machine. atop still lacks support for this fundamental building block. Second, atop stores data on disk with custom delta compression. This works fine under normal circumstances, but under heavy resource pressure the host is likely to lose data points. Since delta compression is in use, huge swaths of data can be lost for periods of time where the data is most important. Third, the user experience has a steep learning curve. We frequently heard from atop power users that they love the dense layout and numerous keybindings. However, this is a double-edged sword. When someone new to atop wants to debug a production issue, they’re solving two problems at once now: the issue at hand and how to use atop."