[root@s101 /usr/pgsql-13/bin]#./pg_controldata --help pg_controldata displays control information of a PostgreSQL database cluster. Usage: pg_controldata [OPTION] [DATADIR] Options: [-D, --pgdata=]DATADIR data directory -V, --version output version information, then exit -?, --help show this help, then exit If no data directory (DATADIR) is specified, the environment variable PGDATA is used. Report bugs to <pgsql-bugs@lists.postgresql.org>. PostgreSQL home page: <https://www.postgresql.org/> [root@s101 /usr/pgsql-13/bin]#./pg_controldata -V pg_controldata (PostgreSQL) 13.3 [root@s101 /usr/pgsql-13/bin]#./pg_controldata -D /var/lib/pgsql/13/data pg_control version number: 1300 Catalog version number: 202007201 Database system identifier: 6976551490179738241 Database cluster state: in production pg_control last modified: Mon 28 Jun 2021 01:10:41 PM CST Latest checkpoint location: 0/161EAC0 Latest checkpoint's REDO location: 0/161EA88 Latest checkpoint's REDO WAL file: 000000010000000000000001 Latest checkpoint's TimeLineID: 1 Latest checkpoint's PrevTimeLineID: 1 Latest checkpoint's full_page_writes: on Latest checkpoint's NextXID: 0:488 Latest checkpoint's NextOID: 14173 Latest checkpoint's NextMultiXactId: 1 Latest checkpoint's NextMultiOffset: 0 Latest checkpoint's oldestXID: 479 Latest checkpoint's oldestXID's DB: 1 Latest checkpoint's oldestActiveXID: 488 Latest checkpoint's oldestMultiXid: 1 Latest checkpoint's oldestMulti's DB: 1 Latest checkpoint's oldestCommitTsXid:0 Latest checkpoint's newestCommitTsXid:0 Time of latest checkpoint: Mon 28 Jun 2021 01:10:41 PM CST Fake LSN counter for unlogged rels: 0/3E8 Minimum recovery ending location: 0/0 Min recovery ending loc's timeline: 0 Backup start location: 0/0 Backup end location: 0/0 End-of-backup record required: no wal_level setting: replica wal_log_hints setting: off max_connections setting: 100 max_worker_processes setting: 8 max_wal_senders setting: 10 max_prepared_xacts setting: 0 max_locks_per_xact setting: 64 track_commit_timestamp setting: off Maximum data alignment: 8 Database block size: 8192 Blocks per segment of large relation: 131072 WAL block size: 8192 Bytes per WAL segment: 16777216 Maximum length of identifiers: 64 Maximum columns in an index: 32 Maximum size of a TOAST chunk: 1996 Size of a large-object chunk: 2048 Date/time type storage: 64-bit integers Float8 argument passing: by value Data page checksum version: 0 Mock authentication nonce: 4731bcc14389812ecb68802b7052a257472e2a01dd2ad374396de3e902bbe940