Does anybody have an idea why we have these hourly spikes in CPU usage on our Amazon RDS database? We don't have any crons running every hour so it seems to be some internal RDS stuff because it's exactly every hour.
We have a number of RDS instances running, from micros up to larges, and I don't see this pattern anywhere - so I suspect that it is something in your code.
Probably the best option to figure out what is going on is to be logged into the database at the top of the hour, and monitor what is connecting and what they're doing. For mysql, you can probably start with SHOW FULL PROCESSLIST. There are monitoring tools that will monitor this for you.
You can enable slow and general log on MySQL server and analyze them using pt-query-digest
also there are some commercial tools like MEM and MONyog which can be handy in monitoring SQL queries.
