1928:20211005:045440.479 housekeeper [deleted 0 hist/trends, 0 items/triggers, 18029 events, 169 problems, 0 sessions, 0 alarms, 0 audit, 0 records in 44895.761061 sec, idle for 1 hour(s)]

  1928:20211004:211956.063 slow query: 17611.322038 sec, "delete from events where (eventid ...

  1928:20211005:002622.993 slow query: 11186.895792 sec, "delete from events where (eventid ...

  1928:20211005:015255.291 slow query: 5192.229874 sec, "delete from events where (eventid ...

  1928:20211005:045438.434 slow query: 10900.706001 sec, "delete from events where (eventid ...

zabbix_db=> EXPLAIN ANALYZE delete from events where eventid=7755800;
                                                        QUERY PLAN
--------------------------------------------------------------------------------------------------------------------------
 Delete on events  (cost=0.43..5.45 rows=1 width=6) (actual time=1.130..1.131 rows=0 loops=1)
   ->  Index Scan using events_pkey on events  (cost=0.43..5.45 rows=1 width=6) (actual time=1.098..1.100 rows=1 loops=1)
         Index Cond: (eventid = 7755800)
 Planning Time: 0.069 ms
 Trigger for constraint c_alerts_2 on events: time=1.002 calls=1
 Trigger for constraint c_alerts_5 on events: time=0.083 calls=1
 Trigger for constraint c_acknowledges_2 on events: time=0.934 calls=1
 Trigger for constraint c_event_tag_1 on events: time=1.630 calls=1
 Trigger for constraint c_problem_1 on events: time=0.075 calls=1
 Trigger for constraint c_problem_2 on events: time=0.038 calls=1
 Trigger for constraint c_event_recovery_1 on events: time=0.844 calls=1
 Trigger for constraint c_event_recovery_2 on events: time=0.425 calls=1
 Trigger for constraint c_event_recovery_3 on events: time=0.055 calls=1
 Trigger for constraint c_event_suppress_1 on events: time=0.063 calls=1
 Trigger for constraint c_alerts_6 on acknowledges: time=8467.500 calls=1  <-- here
 Execution Time: 8473.814 ms
(16 行)

zabbix_db=> EXPLAIN ANALYZE delete from events where eventid=8331312;
                                                        QUERY PLAN
--------------------------------------------------------------------------------------------------------------------------
 Delete on events  (cost=0.43..5.45 rows=1 width=6) (actual time=0.085..0.086 rows=0 loops=1)
   ->  Index Scan using events_pkey on events  (cost=0.43..5.45 rows=1 width=6) (actual time=0.028..0.029 rows=1 loops=1)
         Index Cond: (eventid = 8331312)
 Planning Time: 0.093 ms
 Trigger for constraint c_alerts_2: time=0.043 calls=1
 Trigger for constraint c_alerts_5: time=0.016 calls=1
 Trigger for constraint c_acknowledges_2: time=0.024 calls=1
 Trigger for constraint c_event_tag_1: time=0.018 calls=1
 Trigger for constraint c_problem_1: time=0.016 calls=1
 Trigger for constraint c_problem_2: time=0.014 calls=1
 Trigger for constraint c_event_recovery_1: time=0.018 calls=1
 Trigger for constraint c_event_recovery_2: time=0.091 calls=1
 Trigger for constraint c_event_recovery_3: time=0.017 calls=1
 Trigger for constraint c_event_suppress_1: time=0.021 calls=1
 Execution Time: 0.392 ms
(15 行)

ALTER TABLE `alerts` ADD CONSTRAINT `c_alerts_6` FOREIGN KEY (`acknowledgeid`) REFERENCES `acknowledges` (`acknowledgeid`) ON DELETE CASCADE;

zabbix=> \d alerts;
                                 Table "public.alerts"
    Column     |          Type           | Collation | Nullable |        Default        
---------------+-------------------------+-----------+----------+-----------------------
 alertid       | bigint                  |           | not null | 
 actionid      | bigint                  |           | not null | 
 eventid       | bigint                  |           | not null | 
 userid        | bigint                  |           |          | 
 clock         | integer                 |           | not null | 0
 mediatypeid   | bigint                  |           |          | 
 sendto        | character varying(1024) |           | not null | ''::character varying
 subject       | character varying(255)  |           | not null | ''::character varying
 message       | text                    |           | not null | ''::text
 status        | integer                 |           | not null | 0
 retries       | integer                 |           | not null | 0
 error         | character varying(2048) |           | not null | ''::character varying
 esc_step      | integer                 |           | not null | 0
 alerttype     | integer                 |           | not null | 0
 p_eventid     | bigint                  |           |          | 
 acknowledgeid | bigint                  |           |          | 
 parameters    | text                    |           | not null | '{}'::text
Indexes:
    "alerts_pkey" PRIMARY KEY, btree (alertid)
    "alerts_1" btree (actionid)
    "alerts_2" btree (clock)
    "alerts_3" btree (eventid)
    "alerts_4" btree (status)
    "alerts_5" btree (mediatypeid)
    "alerts_6" btree (userid)
    "alerts_7" btree (p_eventid)
Foreign-key constraints:
    "c_alerts_1" FOREIGN KEY (actionid) REFERENCES actions(actionid) ON DELETE CASCADE
    "c_alerts_2" FOREIGN KEY (eventid) REFERENCES events(eventid) ON DELETE CASCADE
    "c_alerts_3" FOREIGN KEY (userid) REFERENCES users(userid) ON DELETE CASCADE
    "c_alerts_4" FOREIGN KEY (mediatypeid) REFERENCES media_type(mediatypeid) ON DELETE CASCADE
    "c_alerts_5" FOREIGN KEY (p_eventid) REFERENCES events(eventid) ON DELETE CASCADE
    "c_alerts_6" FOREIGN KEY (acknowledgeid) REFERENCES acknowledges(acknowledgeid) ON DELETE CASCADE