amaury@amaury-M15x:~$ sudo npm install -g vtop
npm WARN deprecated graceful-fs@3.0.8: graceful-fs v3.0.0 and before will fail on node releases >= v7.0. Please update to graceful-fs@^4.0.0 as soon as possible. Use 'npm ls graceful-fs' to find it in the tree.
/usr/local/bin/vtop -> /usr/local/lib/node_modules/vtop/bin/vtop.js
/usr/local/lib
└── vtop@0.5.5