PG_CTL(1)

📦 version 16.15, in opensuse-leap 16.0

💖 pg_ctl(1) — PostgreSQL 16.15 Documentation 💖

okay so this is pg_ctl(1), bestie — your server-wrangling bestie from the PostgreSQL 16.15 docs. She initializes, starts, stops, and generally controls a PostgreSQL server, and she's lowkey carrying the whole “please don't leave your logs in the terminal” agenda. ✨

✨ NAME ✨

pg_ctl — initialize, start, stop, or control a PostgreSQL server. periodt. 💅

🦋 SYNOPSIS 🦋

pg_ctl init[db] [-D datadir] [-s] [-o initdb-options]

pg_ctl start [-D datadir] [-l filename] [-W] [-t seconds] [-s]
       [-o options] [-p path] [-c]

pg_ctl stop [-D datadir] [-m s[mart] | f[ast] | i[mmediate]] [-W]
       [-t seconds] [-s]

pg_ctl restart [-D datadir] [-m s[mart] | f[ast] | i[mmediate]] [-W]
       [-t seconds] [-s] [-o options] [-c]

pg_ctl reload [-D datadir] [-s]

pg_ctl status [-D datadir]

pg_ctl promote [-D datadir] [-W] [-t seconds] [-s]

pg_ctl logrotate [-D datadir] [-s]

pg_ctl kill signal_name process_id

On Microsoft Windows, also:

pg_ctl register [-D datadir] [-N servicename] [-U username]
       [-P password] [-S a[uto] | d[emand]] [-e source] [-W]
       [-t seconds] [-s] [-o options]

pg_ctl unregister [-N servicename]

🌸 DESCRIPTION 🌸

Bestie, pg_ctl is a utility for initializing a PostgreSQL database cluster, starting, stopping, or restarting the PostgreSQL database server (postgres(1)), or displaying the status of a running server. Like, yes, the server can be started manually, but pg_ctl encapsulates tasks such as redirecting log output and properly detaching from the terminal and process group. It also provides convenient options for controlled shutdown. Iconic, honestly. 🔥

  • init / initdb mode — creates a new PostgreSQL database cluster, that is, a collection of databases that will be managed by a single server instance. This mode invokes the initdb command. See initdb(1) for details. 🎀
  • start mode — launches a new server. The server is started in the background, and its standard input is attached to /dev/null (or nul on Windows). On Unix-like systems, by default, the server's standard output and standard error are sent to pg_ctl's standard output (not standard error). The standard output of pg_ctl should then be redirected to a file or piped to another process such as a log rotating program like rotatelogs; otherwise postgres will write its output to the controlling terminal (from the background) and will not leave the shell's process group. On Windows, by default the server's standard output and standard error are sent to the terminal. These default behaviors can be changed by using -l to append the server's output to a log file. Use of either -l or output redirection is recommended. 🦋
  • stop mode — shuts down the server that is running in the specified data directory. Three different shutdown methods can be selected with the -m option:
    • “Smart” mode disallows new connections, then waits for all existing clients to disconnect. If the server is in hot standby, recovery and streaming replication will be terminated once all clients have disconnected.
    • “Fast” mode (the default) does not wait for clients to disconnect. All active transactions are rolled back and clients are forcibly disconnected, then the server is shut down.
    • “Immediate” mode will abort all server processes immediately, without a clean shutdown. This choice will lead to a crash-recovery cycle during the next server start.
⚠️ okay but seriously, “immediate” is giving chaos gremlin energy — it aborts everything immediately and you get a crash-recovery cycle on the next start. Not a cute look, but it is documented behavior. 💀
  • restart mode — effectively executes a stop followed by a start. This allows changing the postgres command-line options, or changing configuration-file options that cannot be changed without restarting the server. If relative paths were used on the command line during server start, restart might fail unless pg_ctl is executed in the same current directory as it was during server start. 😭
  • reload mode — simply sends the postgres server process a SIGHUP signal, causing it to reread its configuration files (postgresql.conf, pg_hba.conf, etc.). This allows changing configuration-file options that do not require a full server restart to take effect. 🫶
  • status mode — checks whether a server is running in the specified data directory. If it is, the server's PID and the command line options that were used to invoke it are displayed. If the server is not running, pg_ctl returns an exit status of 3. If an accessible data directory is not specified, pg_ctl returns an exit status of 4. ⭐
  • promote mode — commands the standby server that is running in the specified data directory to end standby mode and begin read-write operations. 👑
  • logrotate mode — rotates the server log file. For details on how to use this mode with external log rotation tools, see Section 25.3. 🌈
  • kill mode — sends a signal to a specified process. This is primarily valuable on Microsoft Windows which does not have a built-in kill command. Use --help to see a list of supported signal names. 💅
  • register mode — registers the PostgreSQL server as a system service on Microsoft Windows. The -S option allows selection of service start type, either “auto” (start service automatically on system startup) or “demand” (start service on demand). 🪟
  • unregister mode — unregisters a system service on Microsoft Windows. This undoes the effects of the register command. 🧚

💜 OPTIONS 💜

okay bestie, option time. Every flag, every default, no skips. 💖

  • -c, --core-files — Attempt to allow server crashes to produce core files, on platforms where this is possible, by lifting any soft resource limit placed on core files. This is useful in debugging or diagnosing problems by allowing a stack trace to be obtained from a failed server process.
  • -D datadir, --pgdata=datadir — Specifies the file system location of the database configuration files. If this option is omitted, the environment variable PGDATA is used.
  • -l filename, --log=filename — Append the server log output to filename. If the file does not exist, it is created. By default, only the cluster owner can access the log file. If group access is enabled in the cluster, users in the same group as the cluster owner can also read it.
  • -m mode, --mode=mode — Specifies the shutdown mode. mode can be smart, fast, or immediate, or the first letter of one of these three. If this option is omitted, fast is the default.
  • -o options, --options=options — Specifies options to be passed directly to the postgres command. -o can be specified multiple times, with all the given options being passed through. The options should usually be surrounded by single or double quotes to ensure that they are passed through as a group.
  • -o initdb-options, --options=initdb-options — Specifies options to be passed directly to the initdb command. -o can be specified multiple times, with all the given options being passed through. The initdb-options should usually be surrounded by single or double quotes to ensure that they are passed through as a group.
  • -p path — Specifies the location of the postgres executable. By default the postgres executable 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 postgres executable was not found. In init mode, this option analogously specifies the location of the initdb executable. 🔍
  • -s, --silent — Print only errors, no informational messages. 🤫
  • -t seconds, --timeout=seconds — Specifies the maximum number of seconds to wait when waiting for an operation to complete (see option -w). Defaults to the value of the PGCTLTIMEOUT environment variable or, if not set, to 60 seconds. ⏱️
  • -V, --version — Print the pg_ctl version and exit.
  • -w, --wait — Wait for the operation to complete. This is supported for the modes start, stop, restart, promote, and register, and is the default for those modes. When waiting, pg_ctl repeatedly checks the server's PID file, sleeping for a short amount of time between checks. Startup is considered complete when the PID file indicates that the server is ready to accept connections. Shutdown is considered complete when the server removes the PID file. pg_ctl returns an exit code based on the success of the startup or shutdown. If the operation does not complete within the timeout (see option -t), then pg_ctl exits with a nonzero exit status. But note that the operation might continue in the background and eventually succeed. 🫡
  • -W, --no-wait — Do not wait for the operation to complete. This is the opposite of the option -w. If waiting is disabled, the requested action is triggered, but there is no feedback about its success. In that case, the server log file or an external monitoring system would have to be used to check the progress and success of the operation. In prior releases of PostgreSQL, this was the default except for the stop mode. 🙈
  • -?, --help — Show help about pg_ctl command line arguments, and exit.

If an option is specified that is valid, but not relevant to the selected operating mode, pg_ctl ignores it. ✨

🪟 Options for Windows 🪟

  • -e source — Name of the event source for pg_ctl to use for logging to the event log when running as a Windows service. The default is PostgreSQL. Note that this only controls messages sent from pg_ctl itself; once started, the server will use the event source specified by its event_source parameter. Should the server fail very early in startup, before that parameter has been set, it might also log using the default event source name PostgreSQL.
  • -N servicename — Name of the system service to register. This name will be used as both the service name and the display name. The default is PostgreSQL.
  • -P password — Password for the user to run the service as.
  • -S start-type — Start type of the system service. start-type can be auto, or demand, or the first letter of one of these two. If this option is omitted, auto is the default.
  • -U username — User name for the user to run the service as. For domain users, use the format DOMAIN\username.

🌿 ENVIRONMENT 🌿

  • PGCTLTIMEOUT — Default limit on the number of seconds to wait when waiting for startup or shutdown to complete. If not set, the default is 60 seconds. ⏳
  • PGDATA — Default data directory location. 🗂️

Most pg_ctl modes require knowing the data directory location; therefore, the -D option is required unless PGDATA is set.

For additional variables that affect the server, see postgres(1). 💜

🗂️ FILES 🗂️

okay so pg_ctl has like two little files it cares about in the data directory, and honestly they're both kinda iconic in their own way 💅

  • postmaster.pid — bestie, this is THE file. pg_ctl peeks inside this one (in the data directory, obviously) to figure out whether the server is currently running or not. It's giving "are you up or are you ghosting me" energy 👀
  • postmaster.opts — if this file is chillin' in the data directory, pg_ctl (in restart mode specifically, iykyk) will pass the contents of the file as options to postgres, unless you override it with the -o option. Oh and bonus: the contents of this file also get displayed in status mode ✨

🌸 EXAMPLES 🌸

okay this is the fun part, let's get into the actual demos fr fr 🫶

💖 Starting the Server

to start the server and wait until it's actually accepting connections (yes, it waits, we love a considerate king):

$ pg_ctl start

and if you wanna start it on port 5433 and run without fsync? say less:

$ pg_ctl -o "-F -p 5433" start

🛑 Stopping the Server

to stop the server, literally just:

$ pg_ctl stop

and the -m option is your girl for controlling how the server shuts down — like, do you want it to go gentle into that good night or nah:

$ pg_ctl stop -m smart

🔄 Restarting the Server

restarting is almost equivalent to stopping the server and starting it again — except (and this is the glow-up) by default pg_ctl saves and reuses the command line options that were passed to the previously-running instance. so to restart with the same options as before:

$ pg_ctl restart

but bestie, if -o is specified, that replaces any previous options. no merging, no keeping the old vibes, it's a full replacement. so to restart using port 5433 and disabling fsync upon restart:

$ pg_ctl -o "-F -p 5433" restart

👑 Showing the Server Status

here's a sample status output from pg_ctl, so you know exactly what to expect when you ask it what's good:

$ pg_ctl status

pg_ctl: server is running (PID: 13718)
/usr/local/pgsql/bin/postgres "-D" "/usr/local/pgsql/data" "-p" "5433" "-B" "128"

and the second line? that's the command that would be invoked in restart mode. so it's basically pg_ctl showing you the receipts of what it's gonna run next 🔥

👀 SEE ALSO 👀

initdb(1), postgres(1)

that's the whole page bestie, you're officially a pg_ctl girlie now 🎀 this legendary little page came from PostgreSQL 16.15 and it's dated 2026 — go forth and start/stop/restart responsibly 💜🦋

📦 where this page comes from