Announced back in December of 2010, Crankshaft was a great milestone to Chrome's V8 engine. With speed improvements reaching 2x in some instances and apps loading up to 12% faster in others, Crankshaft helped propel Google's browser ahead of its competitors in record time. Google was able to achieve these results by making the compiler only optimize code that was run frequently instead of making it use resources to optimize all code. No need in making the compiler run in all scenarios of using the browser if you only found yourself using the same features all the time, which would mean that the same code would be run each and every time. This reduced the workload on the browser which in turn made it run faster and smoother. That was 5 years ago however and if Google Chrome wanted to continue to stay ahead of the competition, it was going to have to continue to innovate and makes its browser faster and better.