we have a current dedicated box with 8 GBs of RAM ( dual quad core CPU) and our DB has grown over 17 GBs ( over 3 DBs for our application ). Im assuming this is reason enough to move to a machine that has more memory ( putting sharding aside ).
The new box has 48 GBs of RAM. WE have a second dedicated box which we replicate (master slave) our DB to as well. I was considering setting up two instances of our DB (running of their own filesystem) running in parallel on the same box but different ports and sticking mysql proxy in front of it to load balance my read traffic.
My reasoning was i dont see each of our DBs needing over 20-22 GBs of RAM before running into other bottle necks. WOuld running these in parallel and load balancing read traffic to them provide comparable performance to using two dedicate boxes?