InfluxDB is created and used by the monitoring services; start-monitor.py.
If monitoring is not required, these services can be stopped and the influxdb folder delete.
 

This article provides inputs on managing Influx DB used by monitoring services for AS4.x

All Supported Platforms

Here is some info on managing the data stored:
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you could modify the retention policy on the database.
The autogen retention policy is currently used, which has an infinite duration (datastays around forever).

Using the influx command-line utility:
> use database tibco
> alter retention policy autogen on tibco duration 1w
would set the duration to 1 week.

<> for the syntax of duration specifications.
https://docs.influxdata.com/influxdb/v1.7/query_language/spec/#durations

<> for details on "alter retention policy".
https://docs.influxdata.com/influxdb/v1.7/query_language/database_management/#modify-retention-policies-with-alter-retention-policy

For retroactively deleting data older than 1w, you could use
(in the influx command-line utility):

> delete from ftl_metric where time < now() - 1w
> delete from ftl_event where time < now() - 1w
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