what is dns cache

1. Reduce the number of HTTP requestsAccording to statistics, 80% of the end-user response time is spent on the front-end program, and most of the time spent on a variety of page elements, such as style sheets, scripts and flash downloads, reducing

1. First, enter the URL in the browser2. The browser finds the IP address of the domain nameThe DNS lookup process is as follows: Browser cache – The browser caches DNS records for a period of time. Interestingly, the operating system does not tell

Step 1,Enter the URL in the browser Step 2,The browser looks for the IP address of the domain name, indicating, The first step in the navigation is to find the IP address of the accessed domain name. The DNS search process is as follows: Browser

Document directory 1. First, you have to enter the URL in your browser: 2. Search for the IP address of the domain name in the browser 3. the browser sends an HTTP request to the web server 4. Permanent redirect response of the facebook

1. JVM Parameter Optimization The following parameters are common in common production environment Tomcat startup scripts. export JAVA_OPTS="-server -Xms1400M -Xmx1400M -Xss512k -XX:+AggressiveOpts -XX:+UseBiasedLocking -XX:PermSize=128M

The machine is a dual system, respectively Windows XP and CentOS-5.3, the problem is that in Windows network speed is very fast, and then switch to Linux network speed becomes snail crawling as slow, endure for some days. I tried to reinstall the

Baidu 2015 interview: Enter the URL in the address bar of the browser and press Enter. What exactly happened ?, 2015url As a software developer, you will surely have a complete hierarchical understanding of how network applications work. The

Java Network Programming InetAddress class is a class that represents an IP address. InetAddress has no constructor. It uses its static method class to return the InetAddress object. GetByAddresspublic static InetAddress getByAddress (byte [] addr)

Digress:Recently, articles about the. net threshold are very popular in the garden. However, this kind of thing will come out once every time, so soy sauce is too lazy. Of course, I also have some ideas, especially the two days that happened to be

Obtain hostname and fqdn Based on Python Shell. Linux's hostname and fqdn (Fully Qualified Domain Name) have been confusing for a long time. Today we are dedicated to figuring out their usage details. 1. Set hostname/fqdn Setting hostname in Linux

Http://developer.yahoo.com/performance/rules.html Yahoo! The predictional performance team brings best practices to improve web performance. They conducted a series of experiments, developed various tools, wrote a lot of articles and blogs, and

You often need to configure hosts in the development phase, but it is very painful to restart the browser (ie or Firefox) after each configuration. Today, I saw the Firefox extension for clearing DNS Cache written by Xiao dongguo in the new tutorial,

Many people do not know how to resolve public domain names on their own DNS servers. Now let's announce the steps. 1. You must have your own domain name. Therefore, go to the domain name registrar to apply for a registered domain name. Try to find a

1. Ping Command Ping is used to determine whether the local host is connected to another host on the network. According to the default settings, the ping command running on Windows sends four ICMP echo request messages, each containing 32 bytes of

We recommend that you install the firebug and yslow plug-ins in Firefox to facilitate debugging. Golden rule for Web Application Performance Optimization: First optimize the front-end performance, because this is the cost of 80% or more of the end

1. Minimize the number of HTTP requests80% of the end user response time is used to download various content. This part of Time includes images, style sheets, scripts, and Flash on the download page. You can reduce the number of HTTP requests by

Document directory 1. First, you have to enter the URL in your browser: 2. Search for the IP address of the domain name in the browser 3. the browser sends an HTTP request to the Web server 4. Permanent redirect response of the Facebook

Winver --------- check windows wmimgmt. MSC ---- open windows management architecture (Wmi) wupdmgr -------- Windows Update Program wscript -------- Windows Script Host settings write ---------- WordPad winmsd --------- system information wiaacmgr --

  Is Ubuntu slow to access the Internet? That's right! Do not doubt that Ubuntu is indeed slower than windows. Where is the slowness?When you use Firefox in Ubuntu 9.10 to browse the Web page, you will find that the status bar in the lower left

From the user input a Web site to the end of the Web page to show the user, what happened in the middle? This is a simple and complex question.The approximate process is summarized as follows:1. Enter the address2. The browser finds the IP address