Description of "Keep HTTP Connection" and "connection timeout n seconds"

Keep HTTP Connection

Reference the following descriptions on the website:Most Web browsers require the server to keep the connection open in multiple requests. This is called to maintain an HTTP connection. Keep the connection is an HTTP
Specifications, which can significantly enhance server performance. Without it, the browser will have to make a large number of connection requests for pages containing multiple elements (SHAPES. Each element may need to be connected separately. These additional requests and connections require additional server activity and resources, which will reduce the efficiency of the server. They also greatly reduce the speed and response capability of browsers, especially when the network connection speed is slow. Reference from ideal blog,However, it is not enough to understand this. To better understand how to maintain HTTP connections, we also need to understand the concept of non-persistent connections and persistent connections in the HTTP protocol,

 

Connection timeout

 

Connection timeout helps reduce the loss of processing resources consumed by idle connections. When connection timeout is enabled, IIS will execute the following types of connection timeout at the connection level:

• The client has sent data to the server and is idle.
  
• A connection has been established with the server, but the server listener times out when the client does not send data.
  
• Response timeout (based on the configurable minimum number of bytes per second ).
  
• The request times out. It prohibits the client from sending unreasonable slow requests to the server (for example, 1 bit/second ).

To determine whether connection timeout should be set, use the system monitor to record the World Wide Web Publishing Service (WWW Service) and FTP
The current connection, maximum connection, and total number of connection attempts in the service object. Record for a period of time until you fully grasp the general scope; generally, this may take days to a week or longer, and it needs to be repeated on a regular basis. For more information, seePerformance monitoring.

Serverlistentimeout
The configuration database attributes no longer exist.Serverlistentimeout
It has been replaced by the following configuration database attributes:

• Connectiontimeout: Specifies the total time (in seconds) to wait before the server is disconnected from the inactive connection ).
  
• Minfilebytespersec: When
  When IIS responds to a client request,Minfilebytespersec
  This attribute determines the length of time the client receives the entire response. If the client takes too long to receive the entire response, the kernel-mode driver HTTP. sys
  The connection is terminated Based on the timeout value. The timeout value is calculated by dividing the size of the entire response (including the title)
  Minfilebytespersec
  Attribute to obtain the maximum allowed response time (in seconds ). For example
  MinfilebytespersecSet to 2048, then the response size of 2 kb must be in
  Completed in 1 second. The default value is 240.
  Bytes/second. This period of time can prevent the client from sending large response requests (such as file downloads), and then deliberately receives responses at a slow speed, consuming resources on the server, it may even interrupt the services provided to other clients.