Glossary Terms

object cache

An object cache is a layer that stores the results of expensive WordPress database queries in fast memory, usually Redis or Memcached, so repeat requests can skip the database and read the answer straight from memory. WordPress has a built-in version, but it only remembers things for the length of a single page load. To carry results across many page loads you connect a persistent memory store through a small <code>object-cache.php</code> drop-in. Managed hosts like WP Engine and Kinsta set this up for you, and it makes the biggest difference on sites that run the same heavy queries over and over, like WooCommerce product lookups or membership checks.