Monday, August 3, 2015

CH2 & CH3 - High Performance Web Sites

Chapter 2, Rule 2: Use a Content Delivery Network

That is it, use CDN to improve static content delivery, the writer hasn't talked much about hosting Dynamic content on CDN.
One experience i had before with Akamai was to host content that were available only for Authorized & Authenticated users, and actually helped us caching this type of content efficiently; Here is an article that talk about that
http://www.akamai.co.jp/enja/dl/feature_sheets/FS_edgesuite_accesscontrol.pdf 


Chapter 3, Rule 3: Add an Expires Header

  1. Use the Expires header so the browser doesnt have to go to the server to fetch unexpired content
    Expires: Thu, 15 Apr 2020 20:00:00 GMT
  2. Because the Expires header uses a specific date, it has stricter clock synchronization requirements between server and client, that is why a new header has introduced
  3. Cache-Control:max-age has introduced to solve this limitation which take the expiration value in seconds, Cache-Control: max-age=315360000
  4. If both, Expires and Cache-Control max-age, are present, the HTTP specification dictates that the max-age directive will override the Expires header
  5. If we configure components to be cached by browsers and proxies, how do users get updates when those components change? To ensure users get the latest version of a component, change the component’s filename in all of your HTML pages. (another solution is to add a query string with a version number xxx.js?v=123 and update the version, however i found that developers complain that browsers sometimes ignore the query string when it comes to caching, so the safest option is to update the file name)



No comments:

Post a Comment