Type: integer
Default: 30 (30s)
Min: 0 (0s)
Max: 2147483647 (2147483647s)
Unit: seconds (s)
Context: sighup
Restart: false

Write a message to the server log if checkpoints caused by the filling of WAL segment files happen closer together than this amount of time (which suggests that max_wal_size ought to be raised). If this value is specified without units, it is taken as seconds. The default is 30 seconds (30s). Zero disables the warning. No warnings will be generated if checkpoint_timeout is less than checkpoint_warning. This parameter can only be set in the postgresql.conf file or on the server command line.