引言回覆:
Mozilla has traditionally relied on [Talos, Sunspider, Kraken, etc] benchmarks to optimize Firefox. Unfortunately there are two problems with benchmarks: a) it is hard to write good benchmarks (see all of the complaints about Sunspider) b) the most perfect synthetic benchmarks do not completely correspond to actual user usage. Firefox with a well-used profile, anti-viral software, well-aged Windows and 30 addons will not perform the same as it does in our clean benchmarking environment.
For my team this became obvious in Firefox 4 once we started recording Firefox startup times. Turned out that it is easier to work on fixing startup performance than make our synthetic test closely reflect real world startup speed.
http://blog.mozilla.com/tglek/2011/05/13/firefox-telemetry/其實 Google 早就這樣作了.....