Redis and object caching can vastly speed up your WordPress page load times with each subsequent visit. It’s also used by many popular websites like Twitter, Snapchat, GitHub, Pinterest, StackOverflow and many others.

A Quick Refresher: What is Caching?

If a web page is cached, it means that elements of that page such as images, stylesheets, and other content are loaded once, then stored in what’s called a “cache.”
It memorizes what was loaded, creates a static version of it, then can serve that version much faster the next time that page is loaded. The result is faster page load times and less of your server’s resources being used.

Check out how Closrr leverages different layers of caching, to speed up websites up to 60%.

What is Object Caching?

Object caching is a type of server-side caching. This means the caching is administered at the server level, and isn’t controlled by the end user or a system they use for caching.

Object caching stores database query results that have been loaded. Then, it serves them up faster the next time they’re requested so the database doesn’t have to be queried again.

WordPress also has object caching built-in with the WP_Object_Cache class.

The trouble is, the inherent object caching WordPress has isn’t persistent by default. This means that cached data is only stored for as long as the request to the database lasts, which is ultimately no more than for one-page load, and inefficient.

If you were to install and use a persistent object caching solution such as – ehem – Redis, for example, data could be cached for all subsequent page loads, giving your database more of a break.

Benefits of Object Cache

WordPress uses databases to cache internal application objects, along with queries for normal page requests, which causes increased load-times.

Object Cache remembers, or caches, any queries to the server after a WordPress page is loaded for the first time. When another user loads the page, the results are provided from the Object Cache which is stored in memory without querying the database again. This results in much faster page load times, and less server impact on database resources.

Scalable Performance. Object Cache provides an alternative caching backend that resides in memory, rather than a database that stores data on a  drive (SSD). By eliminating the need to access drives, Object Cache avoids seek time delays and can access data in microseconds. This improves performance for dynamic pages and logged-in users.

Who Needs Object Caching?

If your WordPress site is static, and all it needs to load are a stylesheet and some images, for example, you’re not going to see any difference if you use object caching.

Conversely, a dynamic site loads tons of data across pages that are stored in your database, such as user details, categories, links, and other similar data.

As previously mentioned, every time a page loads that content, it sends several database queries. If you use object caching, that data is stored in the cache, and it’s ready to be displayed on the page in the flashes of flashes.

Your database can be queried much less often, and retrieving content from the cache is a lot faster than sending queries to the database.

This results in page loading times that are a lot faster. Your server’s resources are also used more efficiently. This is an especially crucial factor if you’re looking to scale your WordPress website.

So, if your site gets a lot of traffic, or you’re expecting it will soon, and it’s dynamic, you should consider using object caching. Therefore, we have implemented a Redis object caching, as an add-on for your website.