This object assigns a specific metric profile's priority and weight settings to a particular virtual host name and query type combination, with 0 meaning no profile is assigned, falling back to the general default. This is where per-application tuning happens, letting an admin give one hosted application's traffic a latency-focused selection profile while another gets a load-focused one, overriding the device-wide default for just that host. A latency-sensitive streaming service hostname might get assigned a profile weighted heavily toward round-trip time, while a bulk file-download hostname's mapping uses a profile weighted toward server load instead.