How to dramatically reduce the build time:)

[Edison Su]

As a poor man, don't have luxury build machine as Alex has, I find a way may 
help you a little bit to build cloudstack as quick as possible:
mvn -pl `git status --porcelain |sed '/^?/d'| awk '{print $2}' |sed 
's/\/src/$/'|cut -d $ -f 1|uniq |tr "\n" "," |sed 's/,$/,client/'` clean install
It tries to find out what has been changed in your local workspace through git, 
then tell mvn to build corresponding modified maven projects. Not perfect 
though, maybe work for some:)