pg\_archivecleanup

pg\_archivecleanup

1

Application

pg\_archivecleanup

clean up

PostgreSQL

WAL archive files

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 [???](#warm-standby)). 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 [???](#guc-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
