The data you see from The Gathering 2015 will seem "broken up". This is not because we don't have data from the first day, but because the backend was re-written on day 1/2 and this web app only uses the new API.
NMS was set up on March 30th (Monday). Data started pouring in on the 31st.
Ping data is available for the entire event with 1 second resolution.
DHCP data is available only for the last detected DHCP ack (no history, except extensive text-based logs)
Uplink status is available for most of the event, but not exposed here.
Traffic status was temporarily bugged, but is available from late on day 2.
Temperature data is available from day 2.
Plans are being made to ensure that we don't have gaps like these in the future.
It is also worth mentioning that things like switch positions are not logged historically, so you see the final position on the map.
These are internal timers for the NMS frontend. They are provided mainly to debug the frontend. Setting AJAX-triggering counters to ridiculous numbers is not advised (mainly because it causes server load).