• Round-Robin Database Storage Engine (RRD) | FromDual
  In a round-robin database (RRD) usually time-series data like network bandwidth, temperatures, CPU load etc. is stored. The data is stored in the way that system storage footprint remains constant over time. This avoids resource expensive purge jobs and reduces complexity. RRD MySQL does NOT yet provide this kind of storage engine. Although some people were thinking about and some prototypes exists. Nevertheless in this paper it is shown how you can build your own RRD tables: Round-Robin Database Storage Engine (RRD)
  By henrik in Development with database mysql round-robin rrd
• Cymen's Blog : MySQL and Round Robin Database (RRD)
  While looking for a MySQL RRD storage engine, I came across Round-Robin Database Storage Engine (RRD) (pdf) which describes how to setup a MySQL table to act as a RRD. The PDF appears to have been created in February of 2007 but the benchmark result at the end of 600 inserts/second says this was achieved on a 1350 MHz AMD CPU which suggests the article may be older. I replicated the configuration and tested it on my laptop (5400 RPM disk, 2.4 GHz Intel T7700 CPU). With the MyISAM database, a brieft test of about 50k inserts resulted in ~7000 inserts/second. But the 25m max rows means the trigger functionality (the part that makes the table behave like an RRD) wasn’t really tested.
  By henrik in Development with database mysql round-robin rrd

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