What Is Object Caching? Redis vs Memcached Explained

In case you have upgraded the hosting package, compressed the images and enabled browser caching, but your website still remains slow, object caching might help. When it comes to WordPress-based websites and other database-driven sites, object caching can make your webpages load significantly faster while reducing the server load and increasing the performance.

This tutorial will cover all aspects of object caching, from the definition and the mechanism to work, Redis vs. Memcached, and the choice of the best one for you.

What is Object Caching?

It is a type of type of web caching approach that allows you to optimize your site by storing in RAM (your server’s memory) the results of commonly performed queries against the database. Instead of executing queries against the database on each visit to your site, your site will fetch the results from the memory, which is much quicker.

For example, when someone visits your homepage, WordPress usually performs several tens or even hundreds of queries against the database to fetch posts, menu, widgets, and options. Thanks to object caching enabled, most of these results will be stored in the memory, and there will be no need to perform these queries.

This way, you get:

• Faster page load
• No stress on the database
• Reduced server resources usage
• Improved performance of your site during traffic surges

Object caching is highly effective for WordPress, WooCommerce, membership, learning management sites, and other sites with dynamic content.

Object Caching Process

The process can be briefly described in this way:

• A user asks for a page.
• Your app asks the object cache for the object.
• If the object is there, it is returned immediately.
• If not, your app looks for it in the database.
• And stores it in the cache for later use.

Because memory is much faster to access than reading from the database, this is very useful.

Differences between Redis and Memcached

Two of the best caching services are Redis and Memcached. Though both the platforms offer enhancements to web sites, there are some differences between them.

Redis

Redis is an application for database management which acts as a high-end in-memory database management system.

Advantages of Redis

1. Allows storing information even after restarting a server (optional persistency)
2. Allows multiple data types
3. Better for caching objects in WordPress
4. Perfect choice for WooCommerce sites
5. Can manage sessions, queues, and caching at once
6. Replication and clustering

Disadvantages

1. Takes up some more space on a server
2. Has more options for configuration

Memcached

Memcached is a light-weight distributed memory cache system developed especially for quick caching.

Advantages of Memcached

1. Very fast
2. Lightweight
3. Easily configured
4. Low memory consumption
5. Great for basic caching tasks

Disadvantages

1. No persistency
2. Limited functionality
3. Does not support advanced data types
4. All cached information will be lost after restarting a server

Comparison between Redis and Memcached

Which One Is Good For WordPress?

In the case of WordPress sites, Redis is a preferable one.

Redis includes the following features:

• Better compatibility with WordPress plugins
• Persistence in caching
• Boosting WooCommerce
• Greater scalability
• Improved cache handling

However, Memcached continues to be a good option for light applications and web sites whose main priorities are simplicity and speed.

Advantages of Object Caching

The enablement of object caching gives you the following benefits:

1. Higher Website Speed: Now, pages will load faster since redundant database queries become unnecessary.

2. Lower Load On Database: Your MySQL database receives fewer requests, which increases server stability.

3. Improvement Of Core Web Vitals: Object caching allows reducing server response time, and it affects Core Web Vitals positively.

4. Better Handling Of Traffic Peaks: While many users are visiting your site at the same time, cached information helps to prevent the overload of your database.

5. Reduction In The Use Of Hosting Resources: Proper caching may help to decrease CPU and database usage and leave room for other users.

When Is It Necessary To Activate Object Caching?

You can use object caching whenever you have:

• WordPress websites
• WooCommerce websites
• Membership websites
• LMS platforms
• News website
• Forums
• High traffic blogs
• Dynamic web applications

Low traffic static sites will see slight improvements only.

How To Activate Redis Object Caching

Some of the better hosting providers have Redis available.

In general, you should:

• Activate Redis service in your hosting account.
• Use a Redis Object Cache plugin for WordPress.
• Link it to your Redis server.
• Check whether object caching is activated.

If Redis is not offered by your current hosting company, then it is time to find another one which offers more modern options.

At HarmonWeb, we have an optimized hosting infrastructure that is tailored to support performance-based websites.

Object Caching Is Different from Page Caching

It is common practice for website administrators to confuse the two.

Page caching saves the already rendered pages.

Object caching saves query results and PHP objects.

They complement each other in order to deliver optimal website performance. You should try to utilize both.

Best Practices for Object Caching

In order to achieve optimal performance from object caching:

• Go for Redis for WordPress if possible.
• Keep your WordPress core, plugins, and themes up to date.
• Utilize object caching in combination with page caching.
• Use SSD or NVMe hosting environment.
• Constantly check cache performance.
• Do not use unnecessary plugins that will result in database queries.

Conclusion

Caching objects is perhaps one of the best methods that can be used to increase the speed of your site without making any hardware upgrades. Thanks to storing frequently accessed information in the cache, not only will your website become faster but will offer users a great experience as well.

Although Redis and Memcached are both great caching platforms, Redis is always the recommended option for contemporary WordPress websites because of its persistence, flexibility, and perfect compatibility with dynamic sites.

If you need high-speed and reliable hosting services that support performance features, HarmonWeb offers hosting options tailored to boost the speed and performance of your website.