Web Apps / Wordpress

WordPress Performance Checklist

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We have by far the largest RPM repository with NGINX module packages and VMODs for Varnish. If you want to install NGINX, Varnish, and lots of useful performance/security software with smooth yum upgrades for production use, this is the repository for you.
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Use proper testing tools!

First things first. Don’t rely on GtMetrix or PageSpeed Insights. If you absolutely must, test using GTMetrix with proper settings.

The best testing tool for performance would be anything that generates traffic to your website. SEO Spider tools that show request rates are good. One example is SEO Frog Spider. The free version will suffice for testing performance just fine.

We can also recommend the following online tests:

  • WebPageTest.org – it puts an accent onto the Time to First Byte metric, which is great!
  • Test if your images are better with another format by using Cloudinary Website Speed Test
  • Pingdom has a good test which is concentrated on total load time
  • Our own performance test does the job of checking your server via HTTP headers and give you configuration suggestions that can be used by a Linux expert

Sane updates approach

Updating to the latest version of WordPress and its plugins is good.
But the more plugins you have – the more frequent updates will be, and thus having to clear the cache.
Batch your updates instead and instead of relying on automatic updates provided by WordPress, use your own system.
For example, create a cron job that runs upgrades of WordPress and its plugins once a month only.
That means your cache is fully cleared only that often.

Use Sphinx

Sphinx provides significant performance improvement for delivery search results. Supporting plugin.

Don’t use Visual Composer

Visual composer ruins performance with its ajax-ed grids. Each grid block sends a slow POST request to admin-ajax.php which can’t be cached because it includes nonces (security tokens). Bad plugin design!

Choose proper hosting

Needless to say: if you are on shared hosting like GoDaddy, SiteGround, or Dreamhost, etc. – forget about performance. There’s little chance that you can grow the number of website visitors if you stay with a shared hosting plan. There’s nearly zero chance you can earn from your website if you stay with a shared plan.

There’s a 100% guarantee though, that your account may be suspended, in case your website does receive any decent traffic (many visitors).

Don’t worry, you can change hosting easily. Pay the same amount of money and get guaranteed RAM, CPU usage, and bandwidth. All these are features of VPS or dedicated servers.

Budget hosting. VPS

At this time, our recommendation is Linode. Get a 2GB server for only $10 / month. It’s an offering from a very notorious VPS company which has been there for over a decade and known for its stability.

DigitalOcean and Vultr can be considered as well, but they can’t beat the latest Linode’s price offer yet.

Higher end. Dedicated server

We have had a good experience with Hetzner servers.
Another alternative is OVH.

Setup WordPress cron properly

WordPress is usually run on a Linux-powered web server. What’s the best way to run WordPress scheduled tasks on a Linux server? Of course, the answer is – cron service of a Linux server 🙂 Provided you make use of the real Linux service for scheduled tasks and not some emulated PHP-based WordPress calls – you will have increased performance and scheduled tasks will not be missed. We’ve covered this in WordPress cron optimization post.

Enable Conditional HTTP get

Conditional HTTP GET can be implemented in WordPress easily. It allows to preserve the bandwidth and thus allows for faster repeat page access.

Set up Persistent Object Cache

WordPress performance for dynamic pages like WordPress admin can be greatly improved by setting up a general cache powered by Redis.

Use a full page cache plugin, or Varnish

A full-page cache plugin is a must, if you don’t make use of Varnish.
For those, who don’t know what Varnish is – it’s a web accelerator and caching server which is the key component to excellent WordPress performance (read about it below).

Our FPC plugin of choice is W3 Total Cache. We did not select it by rolling the dice. The plugin supports a number of different backends for storing its cache easily. It also comes with Varnish invalidation support, so you can disable W3TC’s own page cache and only use the W3TC plugin for hole-punching Varnish cache automatically, after editing your website content.

Use Varnish

Let’s admit it – PHP frameworks are slow. WordPress is one of the frameworks with dozens of PHP files that are parsed on every page request. Having W3TC cache pages to memory is one thing. Having Varnish cache pages to memory is another – it’s a more scalable approach since you can scale your server to many instances.


AMP stands for Accelerated Mobile Pages.
Use AMP plugin for speeding up visitors who are landing up from Google search.

Client-side optimizations

The client-side optimizations are usually your last worry.

Async your scripts

Make sure to use async attribute for loading javascript:

<!-- Modern browsers will use 'async', older browsers will use 'defer' -->
<script src="//somehost.com/awesome-widget.js" async defer></script>

Obsolete Techniques

Some optimizations become unneeded or even unwanted, as the web evolves. We include them here for historical purposes.

Use Cookieless domain for static files

For better cacheability, configure your nginx + WordPress installation with cookieless domain for images and other static files.

How it’s obsolete: HTTP/2 is supported universally across the web. Headers, including Cookie: are compressed. Moreover, use of multiple domains will negate some of the HTTP/2 performance features, request multiplexing. Depends on your TLS setup and specific browser.

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