postgresql怎么关闭服务器

postgresql关闭服务器的方法：

[postgres@localhost ~]$ pg_ctl stop
waiting for server to shut down.... done
server stopped

pg_ctl stop

$ pg_ctl --help

Usage:
  pg_ctl stop    [-W] [-t SECS] [-D DATADIR] [-s] [-m SHUTDOWN-MODE]

Common options:
  -D, --pgdata=DATADIR   location of the database storage area
  -s, --silent           only print errors, no informational messages
  -t, --timeout=SECS     seconds to wait when using -w option
  -V, --version          output version information, then exit
  -w                     wait until operation completes
  -W                     do not wait until operation completes
  
Options for stop or restart:
  -m, --mode=MODE        MODE can be "smart", "fast", or "immediate"

Shutdown modes are:
  smart       quit after all clients have disconnected
  fast        quit directly, with proper shutdown
  immediate   quit without complete shutdown; will lead to recovery on restart

Allowed signal names for kill:
  ABRT HUP INT QUIT TERM USR1 USR2

pg_ctl stop -m smart

SIGTERM "Smart"模式等待所有客户端断开连接以及任何在线备份结束。如果该服务器是热备，一旦所有的客户端已经断开连接，恢复和流复制将被终止。

pg_ctl stop -m fast

SIGINT "Fast"模式（默认）不会等待客户端断开连接并且将终止进行中的在线备份。所有活动事务都被回滚并且客户端被强制断开连接，然后服务器被关闭。

pg_ctl stop -m immediate

SIGQUIT "Immediate"模式将立刻中止所有服务器进程，而不是做一次干净的关闭。这将导致下一次重启时进行一次崩溃恢复。

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