Several tools help determine project effectiveness. DynaTrace can analyze project applications on Internet Explorer and Firebox browsers to see things like CPU usage over time. Another tool is JSPerf to gather data on a test run multiple times over about five seconds, to determine a base line for speed. Then tweaks are applied and more tests run to determine which changes produce the best result.
A key concept is not to slow down Internet Explorer. If you can keep performance good on slow-performing IE, then you can expect to do well on other browsers. Browserscope tied into JSPerf helps determine this. A test case is applied by dozens of people and the results dumped by JSPerf into Browserscope where the comparative results for many of browsers can be seen. The best way to evaluate performance over time with these projects is to compare your current with past performances. "We are our best competition," Resig states, and people are the key element in any of these operations. Always push for better code.
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