Specifies the file system location of the database files. If this is omitted, the environment variable PGDATA is used.
Append the server log output to filename. If the file does not exist, it is created. The umask is set to 077, so access to the log file from other users is disallowed by default.
Specifies the shutdown mode. mode may be smart, fast, or immediate, or the first letter of one of these three.
Specifies options to be passed directly to postmaster.
The parameters are usually surrounded by single or double quotes to ensure that they are passed through as a group.
Specifies the location of the postmaster executable. By default the postmaster is taken from the same directory as pg_ctl, or failing that, the hard-wired installation directory. It is not necessary to use this option unless you are doing something unusual and get errors that the postmaster was not found.
Only print errors, no informational messages.
Wait for the start or shutdown to complete. Times out after 60 seconds. This is the default for shutdowns.
Do not wait for start or shutdown to complete. This is the default for starts and restarts.
pg_ctl is a utility for starting, stopping, or restarting postmaster, the PostgreSQL backend server, or displaying the status of a running postmaster. Although the postmaster can be started manually, pg_ctl encapsulates tasks such as redirecting log output, properly detaching from the terminal and process group, and additionally provides an option for controlled shut down.
In start mode, a new postmaster is launched. The server is started in the background, and the standard input (stdin) is attached to /dev/null. The standard output (stdout) and standard error (stderr) are either appended to a log file, if the -l option is used, or are redirected to pg_ctl's standard output (not standard error). If no log file is chosen, the standard output of pg_ctl should be redirected to a file or piped to another process, for example a log rotating program, otherwise the postmaster writes its output to the controlling terminal (from the background) and will not leave the shell's process group.
In stop mode, the postmaster that is running on the specified data directory is shut down. Three different shutdown methods can be selected with the -m option: Smart mode waits for all the clients to disconnect. This is the default. Fast mode does not wait for clients to disconnect. All active transactions will be rolled back. Immediate mode will abort without complete shutdown. This will lead to a recovery run on restart, and should therefore be avoided. By the default, stop mode waits for the shutdown to complete.
restart mode effectively executes a stop followed by a start. This allows the changing of postmaster command-line options.
reload mode simply sends the postmaster a SIGHUP signal, causing it to reread its configuration files (postgresql.conf, pg_hba.conf, etc.). This allows changing of configuration-file options that do not require a complete restart to take effect.
status mode checks whether a postmaster is running and if so displays the PID and the command line options that were used to invoke it.
If the file postmaster.opts.default exists in the data directory, the contents of the file will be passed as options to the postmaster, unless overridden by the -o option.
To start postmaster:
$ pg_ctl start |
To start the postmaster, blocking until it comes up, use:
$ pg_ctl -w start |
For a postmaster using port 5433, and running without fsync, use:
$ pg_ctl -o "-F -p 5433" start |
To stop postmaster:
$ pg_ctl stop |
Specifies the shutdown mode: smart, fast, or immediate.
Waits for the postmaster to shutdown.
This is almost equivalent to stopping the postmaster then starting it again, except that pg_ctl saves and reuses the command line options that were passed to the previously running instance. To restart postmaster in the simplest form:
$ pg_ctl restart |
To restart postmaster, waiting for it to shut down and to restart:
$ pg_ctl -w restart |
To restart using port 5433 and disabling fsync after restarting:
$ pg_ctl -o "-F -p 5433" restart |