The author doesn't mention anything about load e.g. queries per second. I wonder if the description is: Huge data set, low usage and very fast response time req

The author doesn't mention anything about load e.g. queries per second. I wonder if the description is: Huge data set, low usage and very fast response time required. There are a host of problems with low traffic stacks including: -Persistent database connections going away and the first user who hits the system having to wait for the web server to connect to the DB. -Cache warmup time taking a long time because it takes a long time to get enough queries for the cache to figure out what needs to be cached. -App server warmups taking a long time. Low traffic means it takes a long time for all apache children (or ruby app server or whatever) to get a hit and compile code into mem so the next request is fast. -And the author's [I'm assuming] problem of systems deciding that low usage means the data can be expired from cache. I find the innodb buffer pool cache to be the best in the business on high traffic sites using the author's configuration. [Random aside: I also use Redis and Memcached in production extensively.]