Q:

Server performance metric tools for LAMP

Any suggestions for tools to monitor page load times/errors and other performance metrics for a PHP application?
I am aware of the FireBug and YSlow tools, but this is for more server monitoring.

A:

There is the classic 'ab' (apachebench) program. More power comes from JMmeter. For server health, I recommend Munin, which can painlessly capture data from several systems and aggregate it on one page. 

