web application performance tuning?

Question by linhong5119: web application performance tuning?
A web site is using Resin, Orale9i, J2EE, Struts.
1. What need to measure/monitoring in order to do the performance tuning?
2. Any good guide for performance tuning?
Thank a lot!

Best answer:

Answer by kenwah
To check performance .. You can check each page loading time, database monitoing and web server performance.

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