Optimized WordPress hosting (9+ practical tips)

This post is not about setting up high-availability, fail-over, clustering, IIS versus Nginx versus Apache, RAID 1, 5, 6, 10, different types of storage, and so on. It's about solving performance issues.

Learn how to optimize your WordPress hosting environment

Optimized WordPress hosting Isn't it true that, when you (start to) develop WordPress websites for clients, and you host them yourself, you find yourself in a situation where you need to know a lot about “stuff” other than WordPress development? In this optimizing WordPress hosting post, I provide 9+ practical tips for you to improve WordPress hosting performance. Especially useful if you plan to develop and host WordPress websites yourself, read on to learn what I've done to optimize my WordPress hosting and how you can do the same! Create your own WordPress optimized hosting!

17 valuable WordPress snippets

When reading Facebook groups like Advanced WordPress (AWP) or WordPress Development Stack Exchange, you often find questions like:

Will it affect the performance of the site if we increase the number of records in wp_posts table by 10000 records? At this moment there are 200 posts.

Of course it will affect performance, doh! :) But, you can do a lot to optimize & tune your server/VPS and WordPress hosting.

Server hardware & separate web and MySQL services

One of the most important tips I can give you: separate services.

Whether you run your WordPress blogs on a VPS or bare-metal server, make sure you separate different server types and services. A lot of problems arise from having both Apache/PHP and MySQL on the same server, because MySQL loves memory. Approximately 80% memory needs to be available to MySQL.

My advice for you is to separate them to two servers, dedicated and optimized for their purpose (web or MySQL). Sure it'll cost you an additional $10/m for an extra DigitalOcean droplet, but trust me: it's worth it.

Isn't it true that, when you (start to) develop WordPress websites for clients, and you host them yourself, you find yourself in a situation where you need to know a lot about "stuff" other than WordPress development? These 10 practical tips helps you tackle the most common performance issues.

MySQL optimization

As always, to tune MySQL you need to run an as high version of MySQL as possible. That means running MySQL 5.7, MariaDB 10.1 or Percona Server 5.6, at the time of this writing. Some MySQL administration experience is recommended for optimizing these settings.

InnoDB storage engine

Make sure your MySQL database tables are using the InnoDB storage engine. Nowadays MyISAM is outdated, just like PHP 5.3/5.4, .NET 3.5 and Windows Server 2012/2008/2003 are. All MySQL optimizations are for the InnoDB storage engine, so switch to that and convert MyISAM tables to InnoDB.

InnoDB Disk I/O performance

First, starting with MySQL 5.5, InnoDB disk i/o performance can be greatly improved by increasing the innodb_write_io_threads and innodb_read_io_threads settings in your MySQL server's my.cnf file. These are very important settings.

Secondly, from MySQL version 5.5.4, you can divide the InnoDB buffer pool into multiple instances with multiple innodb_buffer_pool_instances. However, one important detail to remember is:

This options takes effect only when you set the innodb_buffer_pool_size to a size of 1 gigabyte or more.

MySQL InnoDB performance improvement: InnoDB buffer pool instances

This means that when you are dividing your InnoDB buffer pool into 6 instances, you'll need at least 6 GiB RAM. Please note: innodb_buffer_pool_instances is disabled in MariaDB 10.5, and removed from MariaDB since version 10.6. It is still available in Oracle MySQL though.

InnoDB log file size

It is important to set a proper InnoDB log file size in your my.cnf. You need to make the logs (there are two) big enough to hold at most an hour of so of logs. That is more than enough so that it can reorder the writes to use sequential I/O during the flushing and checkpointing process.

Query cache

MySQL Query Cache is deprecated as of Oracle MySQL 5.7.20, and removed in MySQL 8.0, but it is still available in MariaDB. But I wouldn't recommend using it now, see it's limitations and there's more information in MariaDB's blog post Flexible MariaDB Server Query Cache. If you use it, then flush MySQL query cache from time to time to keep it in optimal shape.

RAM, SSD, and CPU

As said, MySQL loves memory (RAM). Make sure your server has plenty of it, and some more. About 80% of the RAM needs to be available for MySQL, and when you start dividing Innodb_buffer_pool_instances, adding query-cache, and various buffer sizes, RAM consumption increases rapidly.

Because SSD offers the best read/write (disk I/O) performance, SSD's are a must too. If you can, switch to NVME disks.

If you don't need MySQL's binlog -or binary log, then disable it. Having MySQL's binary log enabled will increase read/write operations on your disk, decreasing performance. Do enable the slow query log to identify slow running database queries.

The following example enables the slow query log for queries running three (3) seconds or more:

slow_query_log = 1
long_query_time = 3.000000
slow_query_log_file = /var/log/mysql/slow.log

Through this MySQL slow log, I once found that the autoload column of the wp_options table wasn't indexed. You can fix that easily too: wp_options table autoload index.

Don't save on CPU power, because MySQL likes to use the CPU for heavy calculations as well.

Webserver optimization - PHP

No Apache, Nginx or IIS optimizations here, as I feel the webserver is not often the bottleneck when a WordPress site is slow - but maybe you have a great tip for this? Share a comment!.

PHP Optimization

As with MySQL versions, go with the highest possible version: 5.6.18, or preferably 7.0.3 (at the time of this writing), if all your code is PHP 7 compatible. Some PHP settings need optimization too, I discuss them below:

PHP OPcache

Zend OPcache PHP extension is in PHP nowadays, so why not enable OPcache and use it? I recommend you do. Wait, did I stress out you should enable OPcache? In your php.ini verify the following line is not commented out:

zend_extension = php_opcache.dll

You have to properly configure and optimize OPcache to take fully advantage of this opcode cache.

For IIS, set up WinCache and be sure to disable WinCache opcode cache in favor of OPcache's opcode cache:

extension=php_wincache.dll
wincache.ocenabled = 0
wincache.ocachesize = 0

The .dll-part comes from my Windows Server hosting environment. Because of slow development, I stopped using WinCache on our web servers. OPcache is good enough, even on Windows Server.

Be careful when enabling WinCache server-wide though, it might consume all available memory.

PHP realpath_cache_size

The PHP realpath_cache_size setting sets the size of the realpath cache to be used by PHP (e.g, the file locations on disk). Increasing realpath_cache_size can improve PHP performance a lot, and this value should be increased on systems where PHP opens many files. But you have to test and retest the amount of open files to properly set this directive.

How to set a good PHP realpath_cache_size

Your WordPress Hosting at Warp Speed - img. credits: Christian Daryanto Limas @ flickr

WordPress optimization

The following section will give you some quick tips on how to improve the speed of your WordPress website.

Optimization is key.

Check out my WordPress and MySQL categories to learn more about various WordPress and MySQL optimization techniques, for example: index autoload column wp_options table.
- delete transients regularly (automatically using Pressjitsu's wp-transients-cleaner)
- delete post revisions regularly, delete spam comments and meta-data too
- Optimize WordPress database tables, in the background using a cron or must-use plugin
- Move the database from MySQL to Elasticsearch, especially with large WooCommerce ecommerce WordPress shops. Not only is Elasticsearch much faster than MySQL, it also provides and/or searches that are not possible using the normal WordPress MySQL search (like select all products with tag A and tag C, but not tag B or E).
- Use Redis as a full page cache, or install Varnish Cache and deploy it in front of your web server. (Core Caching Concepts in WordPress is a great article introducing you into WordPress caching - "Caching concepten in WordPress: wat is caching en hoe maakt dit WordPress sneller?", is my Dutch translation on ITFAQ.nl). I once created a DIY CDN using Varnish Cache and Bind geo-location DNS on Digital Ocean droplets, to take Sysadmins of the North global.
Install a cache plugin like WP-Super-Cache or Cache Enabler (they're the cache plugins I prefer, but there are many other cache plugins out there). With WP-Super-Cache and Cache Enabler you can speed up WordPress by serving gzip compressed files.
Use SSL in WordPress, it's the de-facto standard nowadays!

Enable GZIP compression in WordPress .htaccess

The easiest way to enable gzip compression in WordPress, for your images, CSS and JS files, is to add these lines to your .htaccess file in the root WordPress folder:

## ENABLE GZIP COMPRESSION
##
<IfModule mod_deflate.c>
  AddOutputFilterByType DEFLATE text/plain
  AddOutputFilterByType DEFLATE text/html
  AddOutputFilterByType DEFLATE text/xml
  AddOutputFilterByType DEFLATE text/css
  AddOutputFilterByType DEFLATE application/xml
  AddOutputFilterByType DEFLATE application/xhtml+xml
  AddOutputFilterByType DEFLATE application/rss+xml
  AddOutputFilterByType DEFLATE application/javascript
  AddOutputFilterByType DEFLATE application/x-javascript
</IfModule>
## / ENABLE GZIP COMPRESSION ##

If your server supports it, enable BROTLI compression instead of gzip. Set an Brotli output filter in .htaccess:

SetOutputFilter BROTLI_COMPRESS

Be aware that not all plugins and external optimization sites / services recognize Brotli compression yet. You may get notices about not having gzip enabled...

Leverage browser caching

Add the following lines to your WordPress .htaccess to enable browser caching for resources:

## ENABLE EXPIRES HEADERS - LEVERAGE BROWSER CACHING
<IfModule mod_expires.c>
  ExpiresActive On
  ExpiresByType image/jpg "access 1 year"
  ExpiresByType image/jpeg "access 1 year"
  ExpiresByType image/gif "access 1 year"
  ExpiresByType image/png "access 1 year"
  ExpiresByType text/css "access 1 month"
  ExpiresByType text/html "access 1 month"
  ExpiresByType application/pdf "access 1 month"
  ExpiresByType text/x-javascript "access 1 month"
  ExpiresByType application/x-shockwave-flash "access 1 month"
  ExpiresByType image/x-icon "access 1 year"
  ExpiresDefault "access 1 month"
  # Web feeds
  ExpiresByType application/atom+xml "access plus 1 hour"
  ExpiresByType application/rss+xml "access plus 1 hour"
</IfModule>
## ENABLE EXPIRES HEADERS - LEVERAGE BROWSER CACHING

Enable HTTP Connection keep-alive

Set the following header directive in your .htaccess file to enable HTTP Connection keep-alive:

Header set Connection keep-alive

Remember that for everything you add to your .htaccess file to optimize WordPress, you don't have to install a plugin! This saves on PHP files and CPU processing time. Win win!

WordPress development tips - DevOps :)

An area I'm not very experienced in, but here goes... A tip: always (try to) follow WordPress development guidelines. For optimized PHP code, check out the PHP Benchmark tests, it's a real must! Also, it's recommended to try to avoid catching exceptions in PHP. Exception handling can cause a performance penalty: Checking the performance of PHP exceptions, Speed performance of Trying and catching Exceptions in PHP.

Try to create your own Windows 11/10 and WSL 2 DevOps environment.

Conclusion

When you develop WordPress websites for clients, and you want to host them yourself, you find yourself in a situation where you need to know a lot about systems administration "stuff". Completely different topics than WordPress development. Like MySQL configuration, web server configuration, PHP settings, server security, performance & optimization, and so on.

I often receive, and read about, questions from developers saying their hosting performance has degraded drastically over the course of time, and have no idea how to resolve the performance issues. In this optimized WordPress hosting post, I provided 9+ important and practical tips to improve your WordPress hosting performance. This post tackled most of your performance issues by explaining those important configuration settings for PHP & MySQL, server & security. Especially useful when you plan to host WordPress websites yourself.

As you might have noticed, MySQL optimization is very important for your hosting environment. If you have a valuable tip, please do share! And don't forget to share this post with your friends and co-workers, thanks!