The Legend of Long JVM Startup Times


Originally published at:
One of the most common complaints about the JVM is the long startup time. But what is really taking so long? We analyze some commands to find out.


Really informative stuff.

A little bit orthogonal to Clojure startup on the JVM are the Clojurescript implementations planck (OS X Javascript Core based) and lumo (cross platfrom Node.js based).

When startup time really does matter and is a significant part of program performance, e.g. command line tooling and scripting, lumo or planck can be a great choice.

$ time lumo -e 'nil'

real	0m0.151s
user	0m0.121s
sys	0m0.023s