Image Packaging System

The Image Packaging System, also known as IPS 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 and a growing number of layered applications, including GlassFish, across a variety of OS platforms.

Features include:

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.

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.

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