For sites concerned with high traffic, speed for logged-in users, or dynamic pageloads, a high-speed and persistent object cache is a must. You also need something that can scale across multiple instances of your application, so using local file caches or APC are out.
Redis is a great answer, and one we bundle on the Pantheon platform. This is our plugin for integrating with the cache, but you can use it on any self-hosted WordPress site if you have Redis. Install from WordPress.org or Github.
It’s important to note that a persistent object cache isn’t a panacea — a page load with 2,000 Redis calls can be 2 full seconds of object cache transactions. Make sure you use the object cache wisely: keep to a sensible number of keys, don’t store a huge amount of data on each key, and avoid stampeding frontend writes and deletes.
Go forth and make awesome! And, once you’ve built something great, send us feature requests (or bug reports). Take a look at the wiki for useful code snippets and other tips.
WP-CLI Commands
This plugin implements a variety of WP-CLI commands. All commands are grouped into the wp redis namespace.
$ wp help redis
NAME
wp redis
SYNOPSIS
wp redis <command>
SUBCOMMANDS
cli Launch redis-cli using Redis configuration for WordPress
debug Debug object cache hit / miss ratio for any page URL.
enable Enable WP Redis by creating the symlink for object-cache.php
info Provide details on the Redis connection.
Use wp help redis <command> to learn more about each command.
Contributing
See CONTRIBUTING.md for information on contributing.