By CDNetworks, Special for USDR
A CDN (content delivery network) service is intended to accelerate web page load times, however numerous factors could be slowing down your web site or web application despite using a CDN. If you are evaluating or using a CDN, here are four things to consider why you are not seeing the improved performance that you want.
Insufficient hardware resources
A CDN offloads traffic from your web server, however your server hardware may still not be able to keep up even with the lightened web traffic. If you are still seeing CPU and RAM usage spikes, you might need to add or upgrade your hardware resources.
Software bugs or misconfigurations can also cause CPU spikes and memory leaks. Make sure you have the latest OS and software patches on your server and check to see if all your server configurations are correct.
An accident on a freeway can cause delays for many miles on multiple routes. Although a CDN is supposed to provide a more reliable and efficient network, the networking issues with your server’s ISP could be causing a bandwidth bottleneck. Occasional outages on the Internet can also cause delays even if you have a CDN such as submarine communications cable accidentally being severed, natural disasters, thieves stealing fiber optic cables, DDoS attacks, and ISP routing issues and hardware outages.
Third party objects
Improper cache settings
The more objects you can cache from your site, the higher the benefits you can receive from a CDN. Caching should not be taken lightly. Some objects should not be cached, such as html files and scripts that needs to be updated frequently. You can set lower cache-control ages for objects that needs to be updated frequently, but having low cache-control ages for static objects that do not change frequently will not optimize your CDN utilization. If you have a low traffic page you might require a longer cache-control age. If an object’s cache-control age has expired, the next request will have to go back to the server instead of the CDN’s edge.
Watch out for conflicting Pragma headers. If you have a cache-control header to cache an object for a month, but you also have Pragma headers with “no-cache”, your cache-control header setting might be overridden. This mistake might occur because of legacy settings or misconfigured CMS adding the Pragma headers by accident.
A CDN can overcome the vast majority of issues that cause a website or web application to be slow, but please also consider these four potential reasons that your website may not be performing to its full potential. Contact CDNetworks.com for a website speed test and evaluation.