I was used to clone the NuttX git repository all the time I need a clean copy. But this is not a good idea, because it waste time and increase the network traffic.
Sebastien Loquert gave a suggestion to improve it:
$ sudo mkdir /opt/nuttx $ cd /opt/nuttx $ git clone https://bitbucket.org/nuttx/nuttx $ git clone https://bitbucket.org/nuttx/apps $ cd ~/nuttxspace $ git clone /opt/nuttx/nuttx nuttx $ git clone /opt/nuttx/apps apps $ cd nuttx $ git pull $ cd ../apps $ git pull
This simple tips will reduce the time I waste download the full repository and will reduce the network traffic. It is important if you are using 3G/4G and you pay by amount of the downloaded data.