Image Packaging System

The Image Packaging System, also known as IPS^[1] or pkg(5), is a cross-platform (written in Python) package management system created by the OpenSolaris community in coordination with Sun Microsystems. It is used by Solaris 11, several illumos-based distributions: OpenIndiana, OmniOS, XStreamOS^[2] and a growing number of layered applications, including GlassFish, across a variety of OS platforms.

Features

Features include:

Use of ZFS, allowing multiple boot environments and easy package operation rollbacks
Transactional actions
Support for multiple platform architectures within a single package
Legacy support for SVR4 packages
Extensive search grammar
Remote search capability
Changes-only based package updates
Network package repository
File and network-based package publication
Package operation history
On-disk package format (p5p)
Multi-platform ports for layered applications:
- Broad platform support: Windows, Linux, OS X, Darwin, Solaris, OpenSolaris, illumos and AIX
- Cross-platform update notification and package management Graphical user interfaces.

Advantages

The fact that IPS delivers each single file in a separate shelf with a separate checksum, a package update only needs to replace files that have been modified. For ELF binaries, it computes checksums only from the loaded parts of an ELF binary; this permits e.g. to avoid to update an ELF binary that changed only the ELF comment section.

Trade offs

Due to the fact that IPS delivers each single file in a separate shelf, slow operation is caused when the input source is on a medium with high latency (e.g. internet with higher round trip time or CD/DVD media with slow seeks). People from Bangalore reported OpenSolaris install times of approximately one week over a DSL link in 2009 when the only package server was in California.