In this day and age, an important part of having a successful website is making sure that it loads quickly. Users don’t want to have to wait around for content. Even a delay of a second or two in a page’s loading time can cause people to click away, resulting in lost traffic.
One of the most common ways of dealing with this problem is through page caching. Commonly used with sites like WordPress or Drupal, this technique involves caching pages with static content. To understand why this works, it is helpful to think about what happens when you actually load a page on the Internet.
Every time you load or refresh a page, a lot happens behind the scenes. Not only does the HTML have to load but all of the scripts have to run. That usually means that databases have to be accessed and calls have to be made, which can take a lot of time. Performing all of these actions every time that a page is loaded can cause the site to work much more slowly. On pages with mostly static content, it is usually unnecessary since the content is the same every time these actions are run. That means that time is being wasted for no good reason.
This is where page caching can be useful. By caching the content, all of those actions that occur behind the scenes don’t have to take place every time the page is loaded. Instead, users are simply shown a cached copy of the page. This leads to a lot faster loading times and a better overall experience for users.
When updates are made to the site, however, the cache needs to be cleared so that users can see the changes. Unfortunately, clearing all of the caches at the same time can result in performance issues. Since all of the content has to load again, it can put a real strain on the site, causing it to slow down.
Advanced page caching helps address this issue. Although it is quite complicated to understand, the basic idea behind it is that it allows web developers to manage page caching on a more granular level. This gives them a lot more control over not only the specific content that is cached but also how those caches are cleared.
Fortunately, plug-ins like the Pantheon Advanced Page Cache allow you to take advantage of advanced page caching without having to get too bogged down in all of the details. Once it is installed on the WordPress or Drupal site, the plug-in takes care of the caching automatically using surrogate keys. The surrogate keys are generated by the plug-in itself. You can also add your own for any additional data on the page that is being cached.
Ultimately, the goal of this type of page caching is to help the site load more quickly while avoiding some of the most common problems associated with normal page caching. Using advanced techniques like this makes it possible to cache pages at a more granular level, which can result in a better overall user experience.