Powerpill is a Pacman wrapper that uses parallel and segmented downloading to try to speed up downloads for Pacman. Interally it uses Aria2 and Reflector to achieve this. Powerpill can also use Rsync for official mirrors that support it. This can be efficient for users who already use full bandwidth when downloading from a single mirror. Pacserve is also supported via the configuration file and will be used before downloading from external mirrors. Example: One wants to update and issues a pacman -Syu which returns a list of 20 packages that are available for update totally 200 megs. If the user downloads them via pacman, they will come down one-at-a-time. If the user downloads them via powerpill, they will come down simultaneously in many cases several times faster (depending on one's connection speed, the availability of packages on servers, and speed from server/load, etc.)
A test of pacman vs. powerpill on one system revealed a 4x speed up in the above scenario where the pacman downloads averages 300 kB/sec and the powerpill downloads averaged 1.2 MB/sec.
Powerpill has a single configure file
/etc/powerpill/powerpill.json you can edit to your liking. Refer to the powerpill.json man page for details.
By default, Powerpill is configured to use Reflector to retrieve the current list of mirrors from the Arch Linux server's web API and use them for parallel downloads. This is to make sure that there are enough servers in the list for significant speed improvements.
Rsync support is available for some mirrors. When enabled, database synchronizations (pacman -Sy) and other operations may be much faster because a single connection is used. The rsync protocol itself also speeds up update checks and sometimes file transfers.
To find a suitable mirror with rsync support, use reflector:
reflector -p rsync
Select the mirror nearest you (you may wish to use reflector's "-c" option to limit results to your country) and then update powerpill.json's rsync server field. After that, all official database and packages will be downloaded form the rsync server whenever possible.
For most operations, powerpill works just like pacman since it is a wrapper script for pacman.
To update your system (sync and update installed packages) using powerpill, simply pass the -Syu options to it as you would with pacman:
# powerpill -Syu
Installation of packages
To install a package and its deps, simply use powerpill with the -S option as you would with pacman:
# powerpill -S package
You may also install multiple packages with it the same way you would with pacman:
# powerpill -S package1 package2 package3