26 January 2015: 2ndQuadrant is proud to announce the release of version 1.4.0 of Barman, Backup and Recovery Manager for PostgreSQL.
This major release features file-level incremental backup, a kind of full periodic backup which saves only data changes from the latest full backup available in the catalogue for a specific PostgreSQL server. Depending on the context and the database workload, the data deduplication ratio might easily reach 50-70% per full backup, leading to significant reductions in both backup time and disk space.
PostgreSQL 9.4 users will transparently benefit from the integration of Barman with "pg_stat_archiver" view. In particular, any continuous archiving problem will be immediately spotted by the "barman check" command directly on the source.
Management of WAL files has been improved, by optimising the calculation of WAL statistics, tying archiving with backup and by distinctively managing WAL trashing for exclusive and concurrent backups.
Relevant efforts in unit testing have made the code more robust. Minor bugs have also been fixed.
Many thanks for funding towards the development of this release go to BIJ12 (www.bij12.nl), Jobrapido (www.jobrapido.com), Navionics (www.navionics.com), Sovon Vogelonderzoek Nederland (www.sovon.nl), and Subito.it (www.subito.it).
For a complete list of changes, see the "Release Notes" section below.
Incremental backup is a kind of full periodic backup which saves only data changes from the latest full backup available in the catalogue for a specific PostgreSQL server. The main goals of incremental backup in Barman are:
This feature heavily relies on "rysnc" and hard links, which must be therefore supported by both the underlying operating system and the file system where the backup data resides.
The main concept is that two periodic base backups will share those files that have not changed, leading to relevant savings in disk usage. This is particularly true of VLDB contexts and, more in general, of those databases containing a high percentage of read-only historical tables. Barman implements incremental backup through a global/server option, called "reuse_backup", that transparently manages the "barman backup" command. Behaviour can also be changed at runtime through the "--reuse-backup" runtime option for the "barman backup" command.
Barman (Backup and Recovery Manager) is an open source administration tool for disaster recovery of PostgreSQL servers written in Python. It allows your organisation to perform remote backups of multiple servers in business critical environments and help DBAs during the recovery phase. Barman’s most requested features include backup catalogues, incremental backup, retention policies, remote backup and recovery, archiving and compression of WAL files and backups. Barman is distributed under GNU GPL 3.