Timeline description of the Chrome dev Debug network

Original: http://www.cnblogs.com/yjf512/p/3668877.html

When using chrome, there is a network in the F12 developer tool, where each request has a timeline description, and when the mouse is placed there is the following display:

Here are a few indicators in the description in Chrome using the documentation that are described:

Below I use human language to understand: Proxy

The connection time to the proxy server.

For example, I used a switch proxy to build a gae, locally initiated goagent is the proxy server. All of my page requests are goagent with this one, so the time it takes for proxy to interact with Goagent is the time.

DNS Lookup

Obviously, the time of the DNS query, when the local DNS cache is not available, this time may be a length, but for example, once you set the DNS in the host, or the second access, because the browser's DNS cache is still there, this time is 0. Blocking

The local operation time before the browser sends the request, such as checking the cache for page cache. Connecting

The time it takes to establish a TCP connection is equivalent to the client starting from the request to the end of the TCP handshake, including DNS query +proxy time +tcp handshake time. Sending

Send the request time, this time is generally very small, of course, if the POST request, the request body is relatively large, then this time period will be relatively long. Waiting

The time to send the request to the beginning of the receive request.

This time period represents the server processing and returning the data network delay time. The goal of server optimization is to make this time period as short as possible. Receiving

Receive Data time

The returned data is relatively large, then the reception time is larger