PostgreSQL复制的类型
+----------------------------------------------------+
| |
| Replication in PostgreSQL |
| |
+--+----------------------------------------------+--+
| |
| |
+------v-----+ +-----v-----+
| Physical | | Logical |
+-+--------+-+ +-----+-----+
| | |
| | |
+-------------v--+ +--v----------+ +--------v--------+
| Log Shipping | | Streaming | | Logical |
+----------------+ +-+---------+-+ | Replication |
| | | Slots |
| | +--------+--------+
| | |
| | |
+------------v--+ +--v--------------+ +--------v--------+
| Without | | With Physical | | Subscriptions |
| Replication | | Replication | +-----------------+
| Slots | | Slots |
+---------------+ +-----------------+
PostgreSQL复制的监控
1.standby端
监控wal接收状态：
postgres=# select * from pg_stat_wal_receiver;
-[ RECORD 1 ]---------+----------------------------------------------------------------------------------------------------
pid | 341627
status | streaming
receive_start_lsn | 3F/D7000000
receive_start_tli | 10
received_lsn | 7E/76964000
received_tli | 10
last_msg_send_time | 2020-10-26 14:04:38.760469+08
last_msg_receipt_time | 2020-10-26 14:04:38.760872+08
latest_end_lsn | 7E/76964000
latest_end_time | 2020-10-26 14:04:38.760469+08
slot_name | pgs
sender_host | 20.10.20.10
sender_port | 5433
conninfo | user=repl password=Pg20 host=20.10.20.10 port=5432 sslmode=prefer application_name=pgs
postgres=#
监控wal应用状态：
postgres=# select pg_last_wal_receive_lsn(),pg_last_wal_replay_lsn(),pg_last_xact_replay_timestamp();
-[ RECORD 1 ]-----------------+------------------------------
pg_last_wal_receive_lsn | 7E/7D0813B8
pg_last_wal_replay_lsn | 7E/7D0813B8
pg_last_xact_replay_timestamp | 2020-10-26 14:10:24.973869+08
postgres=#
2.监控primary端
postgres=# select * from pg_stat_replication;
-[ RECORD 1 ]----+-----------------------------
pid | 210004
usesysid | 16384
usename | replicator
application_name | pgs
client_addr | 20.10.21.11
client_hostname |
client_port | 42526
backend_start | 2020-10-11 02:20:08.99414+08
backend_xmin |
state | streaming
sent_lsn | 7E/7EAAF568
write_lsn | 7E/7EAAF568
flush_lsn | 7E/7EAAF568
replay_lsn | 7E/7EAAF568
write_lag | 00:00:00.000789
flush_lag | 00:00:00.00126
replay_lag | 00:00:00.001683
sync_priority | 0
sync_state | async
postgres=#
3.监控物理/逻辑复制槽
postgres=# select * from pg_replication_slots;
-[ RECORD 1 ]-------+--------------
slot_name | mylogslot
plugin | test_decoding
slot_type | logical
datoid | 16384
database | bench
temporary | f
active | t
active_pid | 2607
xmin |
catalog_xmin | 356948
restart_lsn | 0/3B44A5A0
confirmed_flush_lsn | 0/3B44A5A0
-[ RECORD 2 ]-------+--------------
slot_name | myreplslot1
plugin |
slot_type | physical
datoid |
database |
temporary | f
active | t
active_pid | 2598
xmin |
catalog_xmin |
restart_lsn | 0/3B44A5D8
confirmed_flush_lsn |
postgres=#
来源：oschina
链接：https://my.oschina.net/u/4406457/blog/4694195