We changed the table structure to InnoDB and moved the database to a dedicated server. We are seeing less than 20% cpu load with old average of about 3-4. We have about 2.5 million uniques per day and 450K videos.
for load balancing you could always setup an SQL cluster and I’m pretty sure you could easily setup a rule based load balancing using last digit of the video ID to determine which front end server handles the request to avoid duplicating your cache.
How much traffic are you pushing with how many videos ?
