manpagez: man pages & more
man pg_xlogdump(1)
Home | html | info | man
pg_xlogdump(1)          PostgreSQL 9.6.6 Documentation          pg_xlogdump(1)




NAME

       pg_xlogdump - display a human-readable rendering of the write-ahead log
       of a PostgreSQL database cluster


SYNOPSIS

       pg_xlogdump [option...] [startseg [endseg]]


DESCRIPTION

       pg_xlogdump displays the write-ahead log (WAL) and is mainly useful for
       debugging or educational purposes.

       This utility can only be run by the user who installed the server,
       because it requires read-only access to the data directory.


OPTIONS

       The following command-line options control the location and format of
       the output:

       startseg
           Start reading at the specified log segment file. This implicitly
           determines the path in which files will be searched for, and the
           timeline to use.

       endseg
           Stop after reading the specified log segment file.

       -b
       --bkp-details
           Output detailed information about backup blocks.

       -e end
       --end=end
           Stop reading at the specified log position, instead of reading to
           the end of the log stream.

       -f
       --follow
           After reaching the end of valid WAL, keep polling once per second
           for new WAL to appear.

       -n limit
       --limit=limit
           Display the specified number of records, then stop.

       -p path
       --path=path
           Specifies a directory to search for log segment files or a
           directory with a pg_xlog subdirectory that contains such files. The
           default is to search in the current directory, the pg_xlog
           subdirectory of the current directory, and the pg_xlog subdirectory
           of PGDATA.

       -r rmgr
       --rmgr=rmgr
           Only display records generated by the specified resource manager.
           If list is passed as name, print a list of valid resource manager
           names, and exit.

       -s start
       --start=start
           Log position at which to start reading. The default is to start
           reading the first valid log record found in the earliest file
           found.

       -t timeline
       --timeline=timeline
           Timeline from which to read log records. The default is to use the
           value in startseg, if that is specified; otherwise, the default is
           1.

       -V
       --version
           Print the pg_xlogdump version and exit.

       -x xid
       --xid=xid
           Only display records marked with the given transaction ID.

       -z
       --stats[=record]
           Display summary statistics (number and size of records and
           full-page images) instead of individual records. Optionally
           generate statistics per-record instead of per-rmgr.

       -?
       --help
           Show help about pg_xlogdump command line arguments, and exit.


NOTES

       Can give wrong results when the server is running.

       Only the specified timeline is displayed (or the default, if none is
       specified). Records in other timelines are ignored.

       pg_xlogdump cannot read WAL files with suffix .partial. If those files
       need to be read, .partial suffix needs to be removed from the file
       name.


SEE ALSO

       Section 30.5, "WAL Internals", in the documentation



PostgreSQL 9.6.6                     2017                       pg_xlogdump(1)

PostgreSQL 9.6.6 - Generated Fri Dec 1 19:38:54 CST 2017
© manpagez.com 2000-2025
Individual documents may contain additional copyright information.