[erikpukinskis]

Unless you are making a video game, or doing high throughput data processing, the JavaScript language is probably not your performance bottleneck.

For the most part performance problems in consumer apps are things like pagination, poor re-use of data structures, over pre-caching, etc.

Instagram never has more than what... 10, 20 elements on the screen? And it's all pretty much text or at most a 10 second video clip. There's no reason even a crappy mobile processor can't handle those elements. It's all a matter of being intelligent about what you put on the screen and when.

There's no need for high performance rich data structures. There's no big data.