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PG_XLOGDUMP(1) PostgreSQL 9.5.0 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
Directory in which to find log segment files. The default is to
search for them in the pg_xlog subdirectory of the current
directory.
-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
--timelime=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 29.5, "WAL Internals", in the documentation
PostgreSQL 9.5.0 2016 PG_XLOGDUMP(1)