How much do you really know about managing high traffic web sites? I was asked an interesting question recently. Here it is:
You are operating a web site that receives about 4 million unique visitors per day from around the world seven days a week, 24 hours per day. The load is spread evenly throughout each day. Performance was starting to become unacceptable. You’ve identified that the current bottle neck was your memcached machines, serving as a back cache to your web front ends. Below is a diagram of your simple architecture. What would you do about the problem without bringing your busy site down?