Flapjack vs RRDtool: What are the differences?
Flapjack: Monitoring notification routing + event processing system. Flapjack is a flexible monitoring notification routing system that handles: alert routing, alert summarisation, your standard operational tasks; RRDtool: High performance data logging and graphing system for time series data. RRDtool lets you log and analyze the data you gather from all kinds of data-sources (DS). The data analysis part of RRDtool is based on the ability to quickly generate graphical representations of the data values collected over a definable time period.
Flapjack and RRDtool can be primarily classified as "Monitoring" tools.
Flapjack and RRDtool are both open source tools. It seems that Flapjack with 656 GitHub stars and 91 forks on GitHub has more adoption than RRDtool with 571 GitHub stars and 199 GitHub forks.