After trying on and off for days to find an easy way to use RRD to keep an eye on server load (found in places like the top and uptime commands or in the /proc/loadavg file), I found this. Its fantastic!
RRD::Simple provides a simple interface to RRDTool's RRDs module. This module does not currently offer fetch method that is available in the RRDs module. It does however create RRD files with a sensible set of default RRA (Round Robin Archive) definitions, and can dynamically add new data source names to an existing RRD file.
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