On: V8 Optimization Killers

[autnecare]

I guess it depends on what you're intent is;

http://jsperf.com/for-in-with-hashtable-like-object/4

[PSeitz → autnecare]

The article states "Code compiled by the optimizing compiler can easily be, say, 100x faster than the code generated by the generic compiler"

So expected a quite more than a factor of 2 ...