Chrome developer tools Timeline and profiles improve Web application performance
Second, reduce the number of HTTP requests
When a user browses to a page, if we load some information into the client cache at one time when the user first accesses, when the user accesses other pages, it can greatly improve the page access speed, because each time the HTTP request is to incur the server cost, the common method is: merge Css,js, and as an external reference So that you can reduce the load again when you visit other pages. Most of the sites are now using the page to use all the pictures on a large map, so as long as the site access, the picture is loaded into the client cache. However, there are special circumstances, for a particularly large number of visits to the site, the home should be considered separately, Yahoo recommends that the homepage of the CSS and JS directly in the page file, rather than external references. because the number of visits to the home page is too large, this can be reduced by two requests. In fact, many domestic portals are doing so.
Chrome developer tools Timeline and profiles improve Web application performance