Q: Copy MySQL to RAM as a poor man’s memcached replacement?
A: Use the the MEMORY storage engine on a read only slave to do your reads from, is exactly what you really want and a sane setup. Forget “dumping it to disk” (?!) or other strange things.
You can even put the slave as another instance on your existing server if you can’t afford to setup a dedicated slave, but properly tuning the MySQL parameters for mostly read workloads will bring a significant performance enhancement too!
Original title and link: MySQL MEMORY as Poor Man’s Memcached Replacement ( ©myNoSQL)