pg_archivecleanup

pg_archivecleanup
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pg_archivecleanup — clean up PostgreSQL WAL archive files

Synopsis

pg_archivecleanup [option...] archivelocation oldestkeptwalfile

Description

+ pg_archivecleanup is designed to be used as an + archive_cleanup_command to clean up WAL file archives when + running as a standby server (see Section 27.2). + pg_archivecleanup can also be used as a standalone program to + clean WAL file archives. +

+ To configure a standby + server to use pg_archivecleanup, put this into its + postgresql.conf configuration file: +

+archive_cleanup_command = 'pg_archivecleanup archivelocation %r'
+

+ where archivelocation is the directory from which WAL segment + files should be removed. +

+ When used within archive_cleanup_command, all WAL files + logically preceding the value of the %r argument will be removed + from archivelocation. This minimizes the number of files + that need to be retained, while preserving crash-restart capability. Use of + this parameter is appropriate if the archivelocation is a + transient staging area for this particular standby server, but + not when the archivelocation is intended as a + long-term WAL archive area, or when multiple standby servers are recovering + from the same archive location. +

+ When used as a standalone program all WAL files logically preceding the + oldestkeptwalfile will be removed from archivelocation. + In this mode, if you specify a .partial or .backup + file name, then only the file prefix will be used as the + oldestkeptwalfile. This treatment of .backup + file name allows you to remove + all WAL files archived prior to a specific base backup without error. + For example, the following example will remove all files older than + WAL file name 000000010000003700000010: +

+pg_archivecleanup -d archive 000000010000003700000010.00000020.backup
+
+pg_archivecleanup:  keep WAL file "archive/000000010000003700000010" and later
+pg_archivecleanup:  removing file "archive/00000001000000370000000F"
+pg_archivecleanup:  removing file "archive/00000001000000370000000E"
+

+ pg_archivecleanup assumes that + archivelocation is a directory readable and writable by the + server-owning user. +

Options

+ pg_archivecleanup accepts the following command-line arguments: + +

-d: + Print lots of debug logging output on stderr. +
-n: + Print the names of the files that would have been removed on stdout (performs a dry run). +
-V --version: + Print the pg_archivecleanup version and exit. +
-x extension: + Provide an extension + that will be stripped from all file names before deciding if they + should be deleted. This is typically useful for cleaning up archives + that have been compressed during storage, and therefore have had an + extension added by the compression program. For example: -x + .gz. +
-? --help: + Show help about pg_archivecleanup command line + arguments, and exit. +

Environment

+ The environment variable PG_COLOR specifies whether to use + color in diagnostic messages. Possible values are + always, auto and + never. +

Notes

+ pg_archivecleanup is designed to work with + PostgreSQL 8.0 and later when used as a standalone utility, + or with PostgreSQL 9.0 and later when used as an + archive cleanup command. +

+ pg_archivecleanup is written in C and has an + easy-to-modify source code, with specifically designated sections to modify + for your own needs +

Examples

On Linux or Unix systems, you might use: +

+archive_cleanup_command = 'pg_archivecleanup -d /mnt/standby/archive %r 2>>cleanup.log'
+

+ where the archive directory is physically located on the standby server, + so that the archive_command is accessing it across NFS, + but the files are local to the standby. + This will: +

+ produce debugging output in cleanup.log +
+ remove no-longer-needed files from the archive directory +