Add 2 more characters in f3 (e.g. two empty spaces in the before return). Right now the way it's written it's still below the limit.

That however does not mean you need have to minify your server code.

Please don't base such decisions on some random microbenchmarks that have 0 connection to the code that you are really running in production.

Instead base these decisions on profiling of your actual application.

As I already said below: it is unlikely you get 70% improvement by removing all the comments in your code. For that you need an app that does nothing but a very hot tight loop calling the same small function that does almost nothing too.