How to avoid CDN performance pitfalls – CDN Part 2

09th April 2015

Part 1 of our CDN performance blog looked at how Content Distribution Networks (CDNs) can affect website performance. Here in Part 2 we discuss our top tips for avoiding CDN pitfalls:

  1. Choose your CDNs (it’s not uncommon for large organisations to use multiple CDNs) carefully in the first place. It’s important to consider how they store content, where they are located, what their capacity is, whether their technology is compatible, how good is their support & security and what their own performance is like for example look at figures and guarantees on their uptime.
  2. Check your CDNs doing a good job – monitoring performance 24/7 from the customer down as it uncovers performance issues caused by your CDN. Look for a solution that enables you to drill down into results for CDN performance for example data on cache hits and misses and reporting of errors by host.
  3. To get a handle on CDN performance, website managers can set up logs within their system to track how much traffic is hitting their origin-site from their CDN:  if there are unexpected peaks, this may be an indication that your site might appear to be slow to users and may be due to the CDN doing background tasks like flushing caches when moving infrastructure around.
  4. In respect to mobile last mile latency, you might want to consider how the New York Times addressed the issue by providing its content in a Facebook wrapper as reported last week.

Our experience with our clients provided us these insights and website managers do need a partner/solution that can identify if they have these issues; we would advise not to assume that because you have a CDN that performance is covered.

Common CDN problems we see:

  • Content served slowly
  • The wrong content served e.g. In a different language
  • Worst case no content served at all