Overview page gives the top level picture of all the servers registered with MONyog. It gives the count of the total servers registered with MONyog, total number of disconnected servers, servers having critical alerts and the servers having warnings. You can further drill down to Servers page with the corresponding categories from the Overview page.
Overview also gives you the top 10 queries across all the servers registered with MONyog based on total execution time and also lists the count and Average latency for each of the queries. The queries are basically filtered from the "sniffer.data" file of all the registered servers. You can click on the queries to get the query details which also gives the list of server names on which the particular query was executed. Clicking on the server names will open Sniffer for that server with the time-range selected as the first seen and the last seen of the query.
Overview data is stored in the directory number '0000' inside the data directory. It contains the SQLite files "events_overview.data" and "sniffer_overview.data" which has the event related information like critical alerts, warning count and query data respectively.