MySQL processes and connections
database, mysql, optimization, php, phpmyadmin
Solution
The blue line shows recently opened connections (i.e. opened since the last sample), while the orange one shows currently opened connections (at the time of sampling). The latter are processes in MySQL (the ones that show when you issue a `SHOW PROCESSLIST` command to MySQL -- it really means active connections)
This means that most connections stay opened for less than your sampling period. This is a good thing.
I am unable to find official documention for this feature.
Problem
I'm using phpmyadmin built-in monitor tools to evaluate the usage of my MySQL db. This graphed has raised my attention: I assume the blue means connections, and the orange processes. I'm trying to get a deep understanding of what this graph actually means, and act accordingly. If I understand correctly, it seems as if I'm creating multiple connections per script (process). What situations can cause such a behavior (in addition to simply calling mysql_connect more than once), and how much does this effect performance?