Use network tools for web performance monitoring.
These network tools provide you with a variety of options to measure performance.
Free Website Test tools by WebSitePulse
These WebSitePulse tools are easy to use and free. You can use them to check whether specific components of your website or server are operating properly and to find out what your end-users are experiencing at any given time. Then, you can easily detect any malfunctions and fix them immediately.