While a CDN is an affordable way to speed up applications, the way you configure your network and origin web server can still affect performance. Adding a CDN to your infrastructure is guaranteed to improve reliability and performance, but the amount of improvements that you receive from a CDN addition depend also on your own web application server. With any web application, you can still experience slowness should you not consider certain configurations and resources available from the origin server.
Insufficient Hardware Resources
Your origin server is the main application server where the CDN pulls data and caches it. Should your server have low resources, even a CDN can’t do enough should you have a spike in traffic. You still need a fast server with enough resources to handle traffic. Low resources such as RAM, CPU and hard drive power will reduce the efficiency of your web application. When you determine that you want to integrate a CDN into your infrastructure, you should also ensure that your main application server also has enough resources to handle the data transferred to the CDN network.
Slow Network Resources
When a CDN server pulls data from your origin server, the speed at which the content can be transferred depends on several factors including your network resources. If you have low bandwidth from shared hosting or you don’t have the network speeds to keep up with demands, you could see a slow transfer of this data.
Bandwidth is especially important when you have large files that must be transferred from your own network to data centers across the CDN network. Most ISPs have efficient bandwidth traffic for customers, but web applications hosted on a local network should have enough bandwidth installed on the local network to transfer large files quickly.
Third-Party Software Installations
Having dependencies in your applications is nothing new for developers, but any third-party additions to your web application should be tested for performance. Some dependencies could be the entire issue for a web application’s performance. Performance issues could also be from third-party tools installed on the web server.
Before installing any dependency or third-party tool on the web server, test it in a staging environment. Performance and any interaction with production software should be tested especially with critical servers.
In some cases, the administrator might have conflicting cache settings where one overwrites the other and changes the cache configurations. These server response settings can be tested after deployment in both staging and production environments.
Once these settings are configured, you can re-test your application and use tools such as Google PageSpeed Insights. With the right server resources and CDN configurations, your website will be fast regardless of seasonal traffic and spikes in popularity.