Thanks for the link. Unfortunately, I learned how little I know about file systems and that even the experts don’t seem to agree on a practical solution which we may possibly use here.
57 times overhead sounds huge. Have you thought about building some package from source? In some of my VMs I use this approach, more specifically:
I do not install the existing package from distro’s repo but I build it from source (in a DispVM), using proper build options to make it run from /usr/local/bin or /opt/bin. Then I place the binaries in a bind-dir or in /usr/local/bin of a dedicated AppVM.
Another approach I use for some small Internet-related packages is to install them at qube’s boot time. In the AppVM’s (DVM’s) /rw/config/rc.local I write:
apt-get --quiet --no-install-recommends --assume-yes install <package>
After that, I configure the , so that it creates its necessary files in ~/.config. Then, my DispVMs using this AppDVM (being also RAM-based with near-zero SSD writes) simply download a few MB at boot time. In my case this is acceptable, considering the DispVM is also supposed to connect to the Internet anyway. That is not a perfect solution but the only sensible overhead is a few MB of download. Obviously, this is not suitable for an offline system, for service qubes or for those with special firewall restrictions.
Speaking of building from source, I wonder if using something like Gentoo would not be a better fit for the granular approach discussed in this thread, as it might allow additional flexibility in configuring where the binaries should be placed.