What your hosting looks like when the cache stops helping

Everyone knows you can cache the hell out of a WordPress site.

Stick a CDN in front of it, cache the pages, make enough of the site static and you can serve a frankly silly amount of traffic without WordPress having to break much of a sweat.

Which is great. We like caching. Cache is king, after all.

But it doesn’t tell you all that much about what happens when WordPress actually has to, you know… generate a page… or do something dynamic (like every single ecommerce site in the world).

So, we decided to test that instead.

What happens when you bypass the page cache?

We ran a load test against an uncached WordPress homepage and gradually increased the number of simulated clients hitting it.

With no cached page ready to hand back, WordPress had to process the requests as they came in.

Here’s what we found out:

We tested two WPMU DEV hosting plans. Dedicated Bronze Plus reached 120 simulated clients under load, while Unlimited Alpha MU reached 100.

For comparison, Bluehost, Flywheel and HostGator reached 50, Cloudways reached 40, WP Engine reached 25 and GoDaddy reached 18. For each competing host, we selected the plan closest to the WPMU DEV price point being tested.

Now, before anyone reads “100 clients” and assumes we’ve built hosting for exactly 100 people and the 101st gets launched into the sun, that’s not what the number means.

These are simulated clients used to increase the load during the test. The useful bit is how the different hosting plans performed under the same kind of uncached traffic.

And once caching was out of the picture, the gap was pretty hard to miss:

The numbers don’t lie! Look at Unlimited GO!

While Unlimited is the main focus here, it wasn’t the highest-performing WPMU DEV option in the test. Dedicated Bronze Plus handled 120 simulated clients, the strongest result in the comparison.

That extra headroom makes Dedicated worth considering for sites with heavier or more consistently dynamic workloads. Unlimited Alpha MU still reached an impressive 100, while offering agencies the flexibility to host multiple sites on one server.

Why bother testing uncached pages?

Because, my friends, not everything happening on a real WordPress site can be served from cache.

Sites have logged-in users, membership areas, dashboards, personalized content, WooCommerce carts and checkouts, and all sorts of requests that need WordPress and the database to get involved.

This becomes particularly relevant if you run an agency and have a pile of client sites to look after.

You’re probably not losing sleep over how quickly one cached homepage can be served in isolation. You’re trying to work out where the next client site is going, how much it’s going to cost you, and whether adding more sites to the same platform is eventually going to come back and bite you.

That’s the bit we’re interested in.

Hosting more sites is great, provided they still work

Unlimited Hosting is designed for agencies who want to host multiple WordPress sites on a single server, rather than paying for hosting one site at a time.

Although this test measures uncached traffic against one site running on the Unlimited server, it does show the amount of dynamic processing headroom that server has under the test conditions.

That headroom is important when you’re managing a growing collection of client sites. After all, logged-in sessions, personalized pages, and other requests that bypass the page cache all draw on the server’s resources. The number of sites a server can support will still depend on traffic, themes, plugins and workloads.

That’s why we wanted to look beyond cached traffic.

And yeah, in our uncached test, Unlimited handled:

2x the uncached load of Bluehost, Flywheel and HostGator
2.5x Cloudways
4x WP Engine
5.6x GoDaddy

Dedicated Bronze Plus went further still, reaching 120 simulated clients.

So, that means you’re not just getting a hosting model that makes it easier to consolidate client sites without adding another per-site bill every time.

You’ve also got some pretty solid evidence of what happens when the cache can’t do all the work for you.

A quick note about the test:

Keep in mind, this was a controlled load test, not a prediction of exactly how every WordPress site will behave.

Themes, plugins, databases and whatever weird and wonderful things you’ve bolted onto WordPress will all, of course, affect real-world performance.

And again, the “clients” here are simulated load-test clients. They’re not total visitors, monthly visits or a hard limit on how many people can use a site.

The point of the test is the comparison: same type of uncached load, different hosting plans, and a veeery noticeable difference in how far they got.

We hate to toot our own horn… but when Unlimited gives us a trumpet solo like this, we can’t help it.

Cached WordPress can make everyone look fast

And that’s fine. Cache your sites. Use a CDN. Do all the usual, sensible, performance stuff.

But take that away for a moment and you get a much more interesting look at what the hosting underneath can actually handle.

Unlimited gives agencies a flexible way to consolidate client sites, while this test provides a useful indication of the server’s ability to handle dynamic, uncached requests.

It doesn’t tell us exactly how many sites a server can support, but it does show that Unlimited Alpha MU had substantial dynamic headroom under the test conditions.

If you’re looking after a growing collection of client sites and want to bring more of them into one place without paying for hosting site by site, that’s a result worth knowing about.

See how Unlimited Hosting works.