We studied three tools in this chapter to load test. Now, it is time to load test some real-world applications. In this section, we will test Magento 2, Drupal 8, and WordPress 4. All these open source tools will have their default data.
We have three VPS configured with NGINX as the web server. One VPS has PHP 5.5-FPM, the second has PHP 5.6-FPM, and the third has PHP 7-FPM installed. The hardware specs for all the three VPS are same, and all applications we will test will have the same data and the same versions.
This way, we will benchmark these applications with PHP 5.5, PHP 5.6, and PHP 7 and take a look at how fast these applications can run on different versions of PHP.
Magento 2 is installed on all VPS, and all the caches are enabled for Magento. PHP OPcache is also enabled. After running the tests, we got an average result for all the three Magento 2 installations, as shown in the following graphs:

In the preceding chart, the vertical line, or Y-axis, shows the transactions per second. As can be seen in the charts, Magento 2 on PHP 7 has 29 transactions per second, while the same Magento 2 installation on the same hardware with PHP 5.6 has 12 transactions per second. Also, on PHP 5.5, the same Magento installation has 9 transactions per second. So, in this case, Magento runs about 241% faster on PHP 7 than PHP 5.6 and about 320% faster than in PHP 5.5. This is a very huge improvement of PHP 7 on both PHP 5.6 and PHP 5.5.
WordPress is installed on all of the three VPS. Unfortunately, there is no default cache embedded into WordPress, and we will not install any third-party modules, so no cache is used. The results are still good, as can be seen in the following graphs. PHP OPcache is enabled.

As can be seen in the preceding graph, WordPress runs 135% faster in PHP 7 than in PHP 5.6 and 182% faster than in PHP 5.5.
We used the same VPS for PHP 5.5, PHP 5.6, and PHP 7. The default Drupal 8 cache is enabled. After load testing the default home of Drupal 8, we got the following results:

The preceding graph shows that Drupal 8 runs 178% faster in PHP 7 than in PHP 5.6 and 205% faster than in PHP 5.5.
In the preceding graphs, all these values are approximate values. If a low-power hardware is used, then smaller values will be generated. If we use a more powerful multiprocessor-dedicated server with the web server and database optimizations, we will get higher values. The point to consider is that we will always get better performance for PHP 7 than PHP 5.6.
A combined graph is shown here, which displays the performance improvements for different applications in PHP 7 over PHP 5.5 and PHP 5.6:
