This dashboard is based on the Core Monitoring logs generated by Datafari, which are inserted by Logstash in Elasticsearch under the "monitoring/logs" index.
It shows the documents distribution in the core.
There is one pie chart by distribution type which are by default doc language, doc type and doc source. As you may have understood, each pie is based on a facet : language, source and extension. You can create more charts, based on other facets by learning how to Kibana works, and how our ELK layout works as well.
The important thing on this dashboard is the selected time frame. You can see it at the top right of the Kibana, it is set to "Today" by default.
There is a really good reason why it is set to this value. Kibana works with time events and we decided by default to have one time event by day. It means that we have only one Elasticsearch document by facet value by day. Thus, those "daily documents" are updated each hour by Datafari when a monitoring iteration happens, and we keep the data to display in Kibana up to date. This also means that if you change the time frame of this dashboard to another value that "Today", the data used by the charts will be wrong. Indeed, the time frame of this dashboard must be set to one time event (so the current day if the time event is daily, the current hour if the time event is hourly, and the current minute if the time event is minutely)
For the moment, the Kibana time event is not configurable from the admin UI of Datafari but only by the code (see ELK layout for a better understanding).