There are many techniques which help organizations improve the performance of their web site and reduce the load on servers. Dynamic Page caching is one of such technique and I will provide a brief overview about this technique used in the Content Management System (CMS) and Content Delivery Network (CDN) world.
Dynamic caching of a webpage reduces the number of requests to the origin infrastructure and improves the Time to First Byte (TTFB) and overall performance.
A common use case would be identifying a first-time user vs returning user and generating content accordingly to increase the conversion rate. Often times, a cookie is set, or can be set, to identify the returning user. CDN can check the cookie presence in the HTTP request and serve its respective HTML content from cache.
Creating Dynamic content on a CMS needs integration of multiple technologies. We have successfully used the HTML Template Language (HTL), introduced with Adobe Experience Manager (AEM) 6.0 as a server-side template system for HTML page in combination with Sling selectors to generate dynamic content. Integration between Dynamic Page Caching and Dynamic CMS Webpage is done by implementing the Apache module mod_rewrite, a very powerful and sophisticated module which provides a way to do URL manipulations. Using rewrite conditions and rewrite rules we can fetch dynamic content from different selectors and map it to the requested URL based on cookie conditions and this will be cached on CDN based on same cookie conditions.
While the web page performance may represent a sub set of the overall transaction it plays a very critical role in improving the overall user experience.