Comprehending 'top' CPU usage
linux, top-command, unix
Solution
In *NIX land, 100% cpu usage is 100% of a SINGLE cpu.
This applies to multi-core processors the same way as true multi-processor computers.
So, you are using 7/8th of your total CPU cycles on mysql.
Problem
What does it exactly mean to have a 350% cpu usage (by a process) on a 4-CPU box? The process is a 'mysqld' which is currently being 'bombarded' by a simulated OLTP scenario. Any pointers appreciated.