An error regarding obtaining metrics with mackerel-plugin-mysql has been fixed

Hello. Mackerel team CRE Inoue (id:a-know) here. This is an announcement regarding an error that was fixed for mackerel-plugin-mysql of the official Mackerel plugin pack.

What was fixed?

The metrics obtainable with mackerel-plugin-mysql are Bytes_sent (mysql.traffic.Bytes_sent) and Bytes_received (mysql.traffic.Bytes_received). These metrics represent the number of bytes sent and received by all clients.

The plugin (1) retrieves the corresponding metrics recorded as the cumulative total value in MySQL and (2) calculates the difference and sends it to Mackerel. When browsing these metrics in Mackerel, the expected unit is bytes/sec. However, a value 60 times larger (the value of bytes/min) than the actual value was being sent. This has been corrected according to the Pull Request linked below. Now, a value that is 1/60 of the previous value will be sent.

What needs to be done?

Today we are updating Mackerel’s official plugin package mackerel-agent-plugins. Be sure to update the mackerel-agent-plugins package with your package management system (yum or apt).

With this update, the values of Bytes_sent (mysql.traffic.Bytes_sent) and Bytes_received (mysql.traffic.Bytes_received) will be sent as 1/60 of the previous values. If you’ve created a monitor for these metrics, please be sure to review the thresholds as well.

We apologize for any inconvenience this may have caused and thank you for your understanding.