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mysqltime-seriesinfluxdb

math operations (add, divide) of two series in influxdb 0.9?

I am using InfluxDB 0.9, graphing with Grafana, mysql plugin installed and working.

I need few key metrics for our system:

innodb_buffer_read_hit_ratio = ( 1 - innodb_buffer_pool_reads/innodb_buffer_pool_read_requests) * 100
innodb_buffer_usage = ( 1 - innodb_buffer_pool_pages_free / innodb_buffer_pool_pages_total) * 100

After reading through docs I find that inner join in InfluxDB 0.9 no longer possible. What are my options? change to another time-series db? Install 0.8?

Solution

  • Functions and mathematical operators can only be applied to field values in the same measurement. If innodb_buffer_pool_reads and innodb_buffer_pool_read_requests are fields in the same measurement, that query will work (although only on a recent nightly build or the eventual 0.10.0 release, due to https://github.com/influxdb/influxdb/issues/4046).