Drupal 8 Performance Improvements
Over the years, websites have gotten (mostly) faster thanks to improvements in CMS, Server technology, Browsers, Protocols, and so on. People have gotten used to the idea that websites are fast. If your website is not fast, users will likely bounce, and Google may ding your page rankings (although they claim not to). Yet we're expected to provide content-rich pages with fancy background videos while maintaining the user experience people have come to expect. Drupal 8 doesn't disappoint when it comes to performance and scalability.
If you’re scratching your head wondering how Drupal 8, with so many advancements and improvements, could actually be faster than Drupal 6/7 meet BigPipe. BigPipe enhances performance by sending the cacheable parts of the page first, then the dynamic/uncacheable parts. Drupal 8 also requires PHP 7.x, which offers a modest performance improvements over PHP 5.x. Finally, Drupal 8 provides a built-in dynamic page cache for logged in users that caches pages minus the personalized parts.
“Modern websites are much more dynamic and interactive than 10 years ago, making it more difficult to build modern sites while also being fast.”
--Dries Buytaert, CEO of Acquia and the creator of Drupal
Modern websites are significantly more dynamic and interactive than they were even 10 years ago. Drupal 8 introduced the concept of “cache tags” that allows much more precise cache invalidations. So, for example, if user “X” makes a change to their phone number, instead of invalidating all user caches, Drupal 8 will only invalidate the cache for user “X”. Smart.
Drupal 8 Scalability Improvements
As mentioned in Drupal 8 Future Proofs Websites with Personalized Content and Architecture for a better Customer Journey, Drupal 8 core ships with RESTful Web Service APIs. With this capability built into core, it's much easier to connect to other applications. The possibilities of how Drupal 8 can be used are practically endless. For example, Drupal can be used to serve content to mobile applications. Other examples might include sharing content with Internet of Things (IoT) devices like wearables. Read How to Decouple Drupal for more information.
Drupal 8 provides scalability in another way via the built-in Multilingual modules. These core Drupal 8 modules allow your site to be translated into different languages easily.
For more information on how Drupal 8 provides better scalability, check out Highly Scalable, and Making Drupal 8 Fly. And let’s not forget that better website performance (probably) means better SEO performance in the form of higher page rankings.