The first tab is named for your game, for example TPS and MSPT for Minecraft, server FPS for Rust, tick rate for Source games. It needs an agent; basic mode cannot see lag.
Server health
Tick or frame time against the game's budget, memory, entities and chunks where the game reports them. A lag spike is a tick or frame over the agent's threshold (for example 250 ms on Rust, 100 ms on Paper). Where the game allows, each spike is charged to the plugin, resource, mod or engine phase responsible, so you can see who costs the most. Folia has no single main thread, so Folia servers show no per-tick spikes.
Network
Ping and failed joins where the game reports them. Player latency is a single metric, player_ping_ms, in every game.
Quietest window
The hour with the fewest players, taken from 28 days of hourly data in your timezone. On Roblox the tab is called Deploy window. Use it to pick a restart time, or let an automation use it.
Experience servers (Roblox)
A Roblox experience runs many short-lived servers. This tab lists the ones running now.
Guides
Find the plugin lagging your Minecraft server, Rust server FPS, FiveM resource CPU, Garry's Mod lag and tick rate explained.