Hi, I am using Rackspace for my CDN. Is the time taken to serve a file the slowest the first time it is requested from a CDN? And is this because the file has to be requested from the Cloud File Container sent to the nearest CDN server and then on again to the original request, a sort of double jump? If this is the case is there a way of pre populating specific CDN servers (specifically London)? Rather crudely I thought maybe I could periodically request each of the image files hosted on my CDN by looping through each of them from a winforms app? This would then force them to be cached on the London CDN. Does this seem sensible? Many thanks, Will
The behavior you describe sounds normal. If the file is not cached on the CDN, it'll need to pull it from the server. i am not sure what is the caching policy for your CDN provider. You should really check w/ Rackspace. Many CDN provider allow you to control how long they cache on different file types.
Will, I use RackSpace Cloud Files too, and Frank is correct, you can set a "time to live" on each container. When you're in Cloud Files/Containers, just click the gear to the left of the container, then hit the "Modify Time to Live (TTL)" link and enter a value in seconds. Most of mine are set to live for a month, though on a few more active containers I have them set to refresh every few days.
