Grafana + InfluxDB Disk Usage Graph from two fields

Hello im very new to grafana und want to show the Disk Usage of the /var/ partition of my openbsd system.

I´ve got two fields in my InfluxDB


Kind regards,

Can you explain how much you have set up already?

The applications are running (Grafana,InfluxDB & Telegraph). Ivo got those two fields in the Database but i have problems to build a panel where Grafana shows me the percent value. I found out that there are systems where you can read the disk usage in percent via snap oid but my system does not have this option.