There are many reasons for a slow WordPress website and one you may not have thought of or investigated is resource usage. Your site may simply need more CPU power or RAM. How can you tell?
Google has been pushing people to create faster websites and has been emphasizing the benefits of a fast site and the drawbacks of a slow one for some time. Put simply, fast sites rank higher in search results than slower sites when all other factors are equal. They rarely are, but if they were, your site would outrank competitors. It is clearly an advantage to have a fast site.
Google Web Core Vitals is the search company’s latest effort to goad website owners into speeding up their sites. Speed is not the only factor, but it is an important one. However, some of the actions you must take to speed up a slow website is beyond novices. Optimizing images by shrinking their size is an easy way to improve website performance, but beyond that, it can get quite technical.
No matter what you do to your website, it may still be slow and this could be because the hardware is insufficient. Like computers, Web servers have CPUs, RAM and disks. More CPUs, more RAM and better disks result in faster website performance.
How can you tell whether your web server has insufficient CPU power or enough RAM? How can you tell if limited hardware is the cause of your site’s poor performance?
View website performance
One way is to log into your web hosting account (not WordPress). Not all web hosts show performance and free WordPress.com will not, but usually the information is in your account somewhere. You just have to find it. I cannot tell you where to look because every web hosting company has a different interface and menus. Yours will be different to mine.
Here is an example of one web host, IONOS. Log into your account and go to Hosting > Performance Level.
Here you can see that except for the rightmost bar, all are green. Just the tip is showing orange. This means that the hardware is coping with the number of website visitors and everything is close to perfect. If there was a lot of orange (delayed requests) or red (aborted requests) then it would indicate a serious problem. It would mean more CPU and RAM is needed.
Further down the page are options to increase performance, which usually means adding CPUs, increasing RAM and the memory limit. Increasing the performance is not necessary in this case, but if it was, it is simply a matter of selecting a more powerful option. It is fairly cheap to boost the performance.
Are you over-paying for performance?
It is possible that you are paying for very high-performance hardware that can cope will huge numbers of simultaneous visitors, but you don’t actually have that many visitors. You could be paying more for your hosting than you need and you might be able to save money while still having a fast and responsive website by downgrading to less powerful hardware.
Logging into Bluehost shows a performance widget on the home page. It looks like this:
As you can see, this website is seriously under-using its hardware. With just 3% CPU usage and 1% RAM usage, the hardware is barely awake. Here is a chart showing usage over time, which is available on a menu.
Bluehost recommends that you keep resource usage below 70% and if your site is anywhere near that red area at the top, it is time to add more CPU power and RAM. Both of these are easily added and a simple slider elsewhere enables you to add extra CPUs and memory.
This website is nowhere near the limit and maybe the site could be switched to a cheaper plan with fewer hardware resources. On the other hand, with such a light workload, the site will be fast and responsive, so maybe it’s best to stick with it. The choice is yours.
Monitor resources: UsageDD WordPress plugin
There is a very simple WordPress plugin called UsageDD (https://wordpress.org/plugins/search/usagedd/) that shows useful information about the resources used, CPU and memory your website requires. There are no settings and nothing to configure, you just go to Plugins > Add New, enter ‘usagedd’ into the search box and then install it and activate it.
When it is active and when you are logged in as an administrator, it displays useful information at the bottom of the browser window. It shows the number of MySQL queries (how many times the WordPress database is accessed) on the left, the amount of memory used on the right, and in the middle are the time to first byte and time required to draw the full page.
How can you use the information? You might want to view the figures with a suspected poor plugin enabled and disabled. You should see lower figures, meaning faster performance, when slow, bloated and poorly written plugins are disabled.
The figures change with every page because of the different content and also the same page will return different values because there may be other people or bots on the site at the same time as you. Refresh the page several times to see different values and take an average.