A page's time to first byte (TTFB) is an important measure of performance. It has an influence on the loading time of your Box and, in turn, the behavior of your page visitors and your Google ranking.
💡 The time to first byte describes the time that passes until the first data byte is exchanged between the web server and the browser.
👆 Google recommends a time of 300 milliseconds or less. The TTFB for an empty WordPress installation on our servers is, on average, 130 milliseconds.
Every plugin and theme running on your WordPress installation increase the time. Extensions updates or changes in their configuration can cause the TTFB to suddenly increase dramatically. Here we show you how to find the culprit and make your site fast again.
Step 1: Take stock, what's happened?
First of all, it's important to understand what recent changes have been made on your Box. Changes include:
New plugins and themes
New interfaces, e.g. to payment providers
Plugin and theme updates
You can easily view information about plugin and theme updates via the plugin administration in the Raidboxes Dashboard. Simply click on the Plugins & Themes tab in your Box overview.
In the Plugins section, you can see when the last update was made for a plugin and can track the last changes.
Step 2: Performance analysis
Now you have to record the loading time of your Box. We recommend using the tool webpagetest.org to measure it.
If you want to compare the current loading time of your Box with the loading time of an earlier version of your site, you need to carry out a separate performance analysis for each version. Otherwise, you won't be able to make a meaningful comparison.
To restore an older version of your site, simply clone a backup of the corresponding version into a new Demo Box. Follow the instructions provided in Clone a Box from a backup.
Use Webpagetest to analyze your Box's performance.
Go to the URL https://www.webpagetest.org and enter your Box URL.
Select a German test server under Test Location, e.g. "Frankfurt, Germany - EC2 (Chrome, Firefox, Opera)
Now open the Advanced Settings menu
Select Connection > Cable (5/1 Mbps 28ms RTT)
Type in 3 for Number of Tests to Run
Select the option First View and Repeat View under Repeat View.
Now click on START TEST in the upper right corner.
Webpagestet now performs the performance measurement.
You will find the TTFB measurement in the first table Page Performance Metrics.
If the duration is significantly higher than the 300ms recommended by Google, you should try to optimize it.
If the TTFB value of your old page is for example 250ms and the value of the new page is 1.2 seconds, then you know the reason for the poor loading time must have been introduced somewhere between these two versions. Based on this knowledge, you can now start troubleshooting.
Step 3: Find the error
Next, you need to identify the plugin or theme responsible for the high TTFB.
⚠️ Important: Always work in a Demo Box when troubleshooting.
Use a process of elimination to find the culprit:
Deactivate all your Box's plugins
Change the theme of your site to the WordPress default theme.
Repeat the performance measurement (the TTFB should now be approx. 130ms).
Now activate your plugins and your original theme one after the other and take another measurement after each activation.
With this trial-and-error procedure, you can reliably identify the extensions responsible for the high TTFB. Pay particular attention to large jumps in the TTFB.
Tip: In our experience, so-called premium themes and plugins are usually responsible for increased TTFBs so it makes sense to test these first.
Step 4: Fix the problem
You now know which plugin or theme is responsible for the high TTFB and have the following options to resolve the problem:
Search for an alternative plugin or theme and test it.
Delete the responsible plugin completely
If available, update the responsible plugin or theme to the latest version.
If the extensions are already running on the latest version, contact the plugin or theme developer directly because a patch may already be planned.