The directory /var/lib/preinstalled-pool contains about 500 mb .deb files. Wondering if that can be deleted, to save some space. Found the answer in the file /etc/apt/sources.list. It’s a bright ‘yes’ it can be deleted. It’s just there for ‘your convenience’. I deleted the line from source.list and removed all files from that dir.
# This is a sources.list entry for a small pool of packages # provided on your preinstalled filesystem for your convenience. # # It is perfectly safe to delete both this entry and the directory # it references, should you want to save disk space and fetch the # packages remotely instead. # deb file:/var/lib/preinstalled-pool/ precise main # # ....