Where can the project optimize performance

1. Reduce the number of http requests
2. Reduce DNS queries
3. Use CDN (ie let users access the nearest node, or obtain resources from the cache or source site)
4. Avoid redirects
5. Lazy loading of pictures; optimization of css sprite (that is, use of Sprite); picture width and height.
6. Reduce the number of DOM elements; reduce the operation of DOM
7. Keep-alive can also be used on the page
8. Compress js, css, fonts and pictures
9. Use iconfont
10. Use external js and css
11. The content of the website is stored using multiple domain names ( a factor that saves cookie bandwidth , another important factor is to save the number of connections to the main domain name , thereby improving the utilization of the client's network bandwidth and optimizing the page response. Because the old browser (IE6 is typical ), For the same domain name, only two HTTP connections are allowed to be maintained at the same time. Distribute requests for resources such as pictures to other domain names, to avoid the not necessarily important content such as large pictures blocking the connection of other subsequent resources on the main domain name ( For example ajax request))
12. Reduce iframe usage
13. Place the script at the bottom of the page
14. Remove useless comments
15. Font cropping