The traffic of our football news syndicating website (Kick News) has been steadily growing a lot since it launched. When we redeveloped it a couple of years ago, we used an in-process cache, by creating an IQueryable extension method that uses an md5 hash of the underlying SQL query as the key. This worked reasonably well, but has it’s obvious problems, such as the caches needing to be refilled when the app pool recycles or when the server is restarted. On our busy site, this means we had to wai…