< 2017-11-23 15:15:20.037 -03 >HINT:  Close open transactions soon to avoid wraparound problems.
< 2017-11-23 15:15:20.048 -03 >WARNING:  oldest xmin is far in the past
< 2017-11-23 15:15:20.048 -03 >HINT:  Close open transactions soon to avoid wraparound problems.
< 2017-11-23 15:15:20.059 -03 >WARNING:  oldest xmin is far in the past

< 2017-11-22 10:25:04.262 -03 >LOG:  database system was shut down at 2017-11-22 10:00:04 -03
< 2017-11-22 10:25:04.387 -03 >LOG:  MultiXact member wraparound protections are now enabled
< 2017-11-22 10:25:04.389 -03 >LOG:  autovacuum launcher started
< 2017-11-22 10:25:04.389 -03 >LOG:  database system is ready to accept connections
< 2017-11-22 10:25:15.910 -03 >WARNING:  there is no transaction in progress
...
< 2017-11-22 10:25:20.259 -03 >WARNING:  oldest xmin is far in the past
< 2017-11-22 10:25:20.259 -03 >HINT:  Close open transactions soon to avoid wraparound problems.

postgres@bchlnx361:pg_log $ ps -fea | grep vacuum
postgres   409   403  0 Nov22 ?        00:00:02 postgres: autovacuum launcher process

maintenance_work_mem = 2280MB
autovacuum_work_mem = -1
autovacuum = on
log_autovacuum_min_duration = 0
autovacuum_max_workers = 2
autovacuum_naptime = 60
autovacuum_vacuum_threshold = 5000
autovacuum_analyze_threshold = 50000
autovacuum_vacuum_scale_factor = 0.01
autovacuum_analyze_scale_factor = 0.05
autovacuum_freeze_max_age = 1000000000
autovacuum_multixact_freeze_max_age = 400000000
autovacuum_vacuum_cost_delay = 20ms
autovacuum_vacuum_cost_limit = -1

zabbix_db=# select tuple_count, dead_tuple_count from pgstattuple('public.triggers');
 tuple_count | dead_tuple_count
-------------+------------------
       73657 |          5161183
(1 row)