In the pastebin question, in the HLD diagram, it talks about Block Cache. What is it referencing here? What would be an example of a block cache? I am guessing that it’s a cache that probably caches content like images or large pieces of text. What would be a real world example of block cache?
Also is it a good idea to always have load Balancers between the Application server and Database/Cache servers? When would we not want to keep an LB between those two?