The text discusses how to use Datadog and DogStatsD to optimize the performance of Memcached in a web application. It covers calculating hit ratios for individual requests, which can be used to evaluate the effectiveness of a cache, and timing requests to verify that Memcached is doing its job. By using these metrics, developers can gain insight into the performance of their cache and make data-driven decisions to optimize it further. The text also highlights the importance of considering other factors beyond hit ratios, such as request overhead and cache serialization costs, when evaluating a cache's effectiveness.