We are hosting our web application http://timr.com on a server located in Germany. The server handles a high load of traffic very well and everything works as desired in terms of performance and load times.
However we sometimes get complaints from our overseas users (US, South America) that the experience slow page loading times.
What would be the best way to test the performance of a web application "as if you are on another continent"? I want to make sure that the distance between the server and the user is no problem?
You can use WebPagetest or Pingdom's Full Page Test to do one-off testing for free. Pingdom also lets you do continuous testing for a fee.
Edit
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Using something like PastMON will allow you to get accurate measurements of real RTT and bandwidth.
Have a look at this question on stackoverflow for how to simulate low bandwidth and/or high latency links. To automate testing have a look at Selenium.
Yahoo Boomerang is great tool for measuring page response times. Add graphite for capturing / presenting the data.