====== Recording Stats at VHS ======

VHS has an InfluxDB/Grafana instance to record and graph datapoints //in the cloud.//

===== InfluxDB =====


**InfluxDB** is a time-series database. What that means, is that it stores data with respect to time.

Consider a MySQL database. Except instead of sending a new value and overwriting the previous data, InfluxDB keeps track of both, along with the time they were sent (unless you specify a different time).

You can also specify "retention policies" that phase out old datapoints, basic arithmetic and soon, some native analytics.

Some use-cases are current temperature, price of Bitcoin, or common "open" times for isvhsopen.com

==== A Dataset Example ====
<WRAP center round box 60%>

{
    "results": [
        {
            "series": [
                {
                    "name": "cpu_load_short",
                    "columns": [
                        "time",
                        "value"
                    ],
                    "values": [
                        [
                            "2015-01-29T21:55:43.702900257Z",
                            0.55
                        ],
                        [
                            "2015-01-29T21:55:43.702900257Z",
                            23422
                        ],
                        [
                            "2015-06-11T20:46:02Z",
                            0.64
                        ]
                    ]
                }
            ]
        }
    ]
}

</WRAP>

==== A sample exploration ====


Login to the InfluxDB interface (linked below)

Select the "api" database in top right

<WRAP center round box 60%>
SHOW SERIES

SHOW MEASUREMENTS

SHOW TAG KEYS FROM "api"

SHOW TAG VALUES FROM "api" WITH KEY = "name"
</WRAP>


===== Grafana =====



**Grafana** takes those datapoints and makes pretty graphs out of them.

===== Links =====


  * InfluxDB: http://stats.vanhack.ca:8083/ - Use "admin" and standard VHS credentials
  * Grafana: http://stats.vanhack.ca:3000/ - Create your own account!
  * Get your head around it: https://docs.influxdata.com/influxdb/v0.9/concepts/key_concepts/
  * Get your hands dirty: https://docs.influxdata.com/influxdb/v0.9/guides/querying_data/
  * Operation scripts for installation details: https://github.com/vhs/vhs-ops-scripts