chrome的Timing参数说明

Resource network timing

The Timing tab graphs the time spent on the various network phases involved loading the resource. This is the same data displayed when you hover over a resource bar in the waterfall view.

Stalled/Blocking

Time the request spent waiting before it could be sent. This time is inclusive of any time spent in proxy negotiation. Additionally, this time will include when the browser is waiting for an already established connection to become available for re-use, obeying Chrome's maximum six TCP connection per origin rule.

Proxy Negotiation

Time spent negotiating with a proxy server connection.

DNS Lookup

Time spent performing the DNS lookup. Every new domain on a page requires a full roundtrip to do the DNS lookup.

Initial Connection / Connecting

Time it took to establish a connection, including TCP handshakes/retries and negotiating a SSL.

SSL

Time spent completing a SSL handshake.

Request Sent / Sending

Time spent issuing the network request. Typically a fraction of a millisecond.

Waiting (TTFB)

Time spent waiting for the initial response, also known as the Time To First Byte. This time captures the latency of a round trip to the server in addition to the time spent waiting for the server to deliver the response.

Content Download / Downloading

Time spent receiving the response data.