You know Facebook suffers from what I've called the "Dirty Restaraunt Theory". People only notice a dirty restaurant, not many people walk in and say "Damn, this is the cleanest facility I've eaten in." Same thing here, for such a behemoth of information, aggregated from so many servers across the world, the untrained user rarely acknowledges the tech wizardry behind the curtain.
Via Facebook Engineering
BrowserLab automatically analyzes the performance of every code change made by engineers at Facebook, catching even the smallest regressions — as small as 20 ms — and ensures that our site continues to load quickly. Since we introduced the system into our workflow, it has helped engineers identify optimizations to remove more than 350 ms from every page load.
Read More here.
