How can I get "delta" packages to optimize apt-get upgrade downloads?

I have recently installed Fedora in VirtualBox and noticed that they use Delta-RPM packages, which help dramatically reduce downloading sizes. Also I heard that Gentoo uses some delta packages. Would be glad to see such deltas in Ubuntu too.

Does anyone know about such delta-deb packages and how do I get to use them?


Solution 1:

You may be looking for debdelta package.

From man debdelta-upgrade:

NAME
       debdelta-upgrade  -  Downloads  all deltas that may be used to 'apt-get
       upgrade', and apply them.

SYNOPSIS
       debdelta-upgrade [OPTION]... [PACKAGE] ...

DESCRIPTION
       This program is designed to download changes (deltas) that may be  used
       to  apt-get upgrade all listed packages, and apply them.  If no package
       is listed in the command line, then it will  apply  to  all  upgradable
       packages. See debdelta(1) for more details on the delta files.

How to use

sudo apt-get update
sudo debdelta-upgrade
sudo apt-get upgrade

Example

$ sudo debdelta-upgrade 
Downloaded, time  7.24sec, speed 212kB/sec, xserver-xorg-video-intel_2.99.910+git20140315.8cc1f005-0ubuntu0sarvatt~saucy_i386.deb
Delta-upgrade statistics:                                                       
 total resulting debs, size 1539kB time 8sec virtual speed 181kB/sec