RAM memory is used by memcache. Our suggested factor is 4. A high CPU usage is not necessarily a bad thing (as long as you don't reach the limit). Memcached runs entirely on RAM memory.
Memcached reduces that load by storing data objects in dynamic memory (think of it as short-term memory for applications). Memcached stores data based on key-values for small arbitrary strings or objects including: Results of database calls.
