HTTP monitor metrics

The following metrics are captured and displayed for synthetic HTTP monitors:

  • Response time: Measures the HTTP monitor or event performance. Response time is the sum of DNS lookup time, TCP connect time, TLS handshake time, Waiting, and Download.

  • DNS lookup time: Amount of time taken to resolve the host name—If there are multiple DNS calls because of a redirect, this is the total time of all DNS calls.

  • TCP connect time: Amount of time taken to establish the TCP connection—If there are multiple TCP connections because of a redirect, this is the total time of TCP connection attempts.

  • TLS handshake time: Amount of time taken to complete the TLS handshake.

  • Waiting: Amount of time taken for the server to respond with the first byte—This is the Time to first byte minus (DNS lookup time + TCP connect time + TLS handshake time).

    Note that Time to first byte is the amount of time from the start of the request until the first byte of the response is received.

  • Download: Amount of time taken to download the HTTP response. Download time can be can be 0 when the response is contained within a single packet. Download time can also be 0 when the network is slow. In such cases, we report network latency in Waiting time.