In this blog, we will discuss WordPress caching; what it does – and how it improves the performance and speed of your website.
What is Caching?
To understand WordPress caching, you first have to understand the concept of caching. Caching refers to the process of storing data in temporary folders where they are easily accessible. It’s primary aim is to reduce processing time and make information available as quickly as possible.
This is especially important in WordPress websites. WordPress websites are dynamic by default, which means that each time a user visits your site, WordPress goes through a series of steps to generate information from your database to show to the visitor.
The benefit of this process is that the user gets a somewhat customized experience, since the pages are generated specifically for them. This benefit has the drawbacks that occur as a result of the long processing time, which can make the website slower.
When it comes to caching specifically in WordPress, it works by following the process of temporarily storing the dynamically generated files of frequently visited pages on your website as static files for easy recollection and use. Caching reduces the demand on your web server to continuously generate dynamic content. This means that when a user visits a page, the page shown to the user is stored exactly how it appeared the last time they visited, so the next time that page is requested, there’s no need for WordPress to generate a new page. It just presents the previously generated page, at a rate that is 3-5 times faster.
There are two types of content available on web pages:
- Static files: As the name implies, static files refer to the types of content that do not change. These types of files include images, javascript files, css stylesheets, and HTML pages. Static content remains the same regardless of the user and is created long before they are needed.
- Dynamic files: Dynamic content is created at the point of request, specifically for the user. This type of content is created based on the user’s location, device and time of request.
WordPress caching is the process of storing these dynamic files as static files, thereby increasing the speed and performance of your website.
There are two basic types of caching – Client-side and server-side.
Client-side Caching
Client-side caching occurs when the temporary caching files are stored on the end user’s device. Modern browsers have the benefit of having smart coding that aims to reduce redundancies by saving static files for future use.
As a result, when users open a web-page, the browser starts downloading static files such as images, HTML pages and other multimedia content. Their browser saves all these files so it doesn’t have to re-download them every time you visit the site in the future.
While this helps with the speed of your browsing, it is recommended that you clean up your cache data once in a while so the files don’t become too bulky and reduce the performance of your browser.
Server-side Caching
Server side caching refers to the caching protocol employed by your WordPress server to save temporary files. There are four possible protocols for WordPress Caching;
- Page caching
- OPcode caching
- Object caching
- CDN Caching
Page Caching
Page caching occurs when your caching plugin – like WP-Optimise – saves the dynamically generated HTML files on your server’s hard disk after the first time it is loaded. Whenever there is another request for that page, your server produces the previously generated data.
OPcode Caching
When a PHP file is loaded on the website, OPcode caching saves the compiled PHP code. For a PHP code to execute, it must be generated and compiled by the PHP compiler. OPcode caching saves the initially generated code on the server’s RAM, to save time upon subsequent requests.
Object Caching
Object based caching saves database queries after the first time they are requested. This way, it reduces PHP execution time and load time when the query is requested again. Since WordPress is a content management system that is reliant on databases, object caching seeks to reduce the load on the database and reproduce previously loaded content faster. This is crucial for high traffic websites. So crucial that WordPress has its own internal caching system that can be enhanced with a third party tool.
CDN Caching
CDN (content delivery network) caching refers to the process of storing web content in proxy servers that are much closer to the end user. By using proxy servers, CDN caching helps your website to deliver content much faster.
How does WordPress Caching improve your WordPress site speed and performance?
WordPress caching increases the speed of your website in three primary ways
Moves files to “recent memory”
You may be aware that computers and computer systems are built to mimic the brain. Caching is a prime example of that.
When you try to remember an event from your childhood, it takes a while before you fully recollect the details. However, if you try to remember that same event days later, you remember the details almost at once. This is because your brain moved the event to a recent memory. It may surprise you to learn that you are not remembering the event, but you are in fact remembering the last time you remembered the event.
Caching adopts this same principle by storing previously loaded web elements in a “recent folder.” As a result, your web pages load faster when they are requested.
Saves files closer to the end user
Another way caching increases the speed of your website is by delivering content that is closer to the user; either from a server close by or from the user’s hard disk. This is a combination of client-side and server-side caching.
Compress images
Caching plugins like WP-Optimize give you the option of compressing your images. Bulky images take more time to load which can slow down the overall speed of your website. With cache plugins, you can manually or automatically compress images to reduce load time.
How Caching boosts performance of your WordPress website
Caching plugins don’t only increase your load speed, but they reduce the workload on your server. The following are the ways by which caching improves your website’s performance
Improves user experience
Consumer attention span reduced from 12 seconds to 8 seconds in just 16 years from 2000 to 2016. There’s an explanation for this; technological advancements, intense competition and over stimulation of the mind from smart devices are the most significant culprits.
This now means that you have only a few seconds to make an impression or lose the user to a potential competitor. Research suggests that slow websites are a huge turnoff to modern day internet users.
There is also a correlation between higher bounce rates and slower pages, which means the longer it takes your page to load, the higher your bounce rate. The ideal page load time is under 2 seconds. A load time beyond 3 seconds can increase page abandonment rate by up to 87%.
Improves ranking
Website speed is a performance and ranking factor for search engines. In recent times, search engines like Google have begun to penalize slow websites. Websites with longer page load times are eventually pushed farther down the pecking order and replaced by faster websites.
Google prioritizes user experience as a ranking factor and site speed is a crucial aspect of the UX. When users get disappointing experiences from the websites search engines direct them to, it reflects poorly on the search engine. Users are then less likely to trust the search engine results if that trend continues.
Boosts content availability
Several factors affect whether or not your website will load for a user. Frequent network interruptions or network congestion for example, are two of those factors. Since WordPress dynamically generates content for the user, this could greatly affect the performance of your website for that user.
Caching solves this problem by providing an already generated page for the end user. This way, you won’t lose a potential or active customer to a poor network connection.
Cleans your database
Caching plugins like WP-Optimize work to clean your database by de-fragmenting MySQL tables and clearing data like trashed comments, expired transient options, pingbacks, etc. This process is important because without it, your website’s performance and speed reduces overtime.
Conclusion
Chances are that you may never get to notice how your website interacts with every end user. You can’t tell what happens when people try to access your website from halfway across the world. But what you can do is ensure that your WordPress site’s performance and speed are optimal at all times. With WordPress caching, you don’t have to lose sleep worrying about all that. Install a reputable plugin like WP-Optimize, and buy yourself some time to focus on other aspects of your business.
Great article, but on section about Page Caching You made a mistake about RAM being hard disk