ceilometer database size keeps increasing and is getting very large

Issue

• Ceilometer sample table keeps increasing and is getting very large:

[root@director ~]# du -sh /var/lib/mysql/ceilometer/
31G /var/lib/mysql/ceilometer/
[root@director ~]# du -sh /var/lib/mysql/ceilometer/sample.ibd 
29G /var/lib/mysql/ceilometer/sample.ibd

• We applied this solution but it didn't work:

MariaDB [ceilometer]> optimize table sample;
+-------------------+----------+----------+-------------------------------------------------------------------+
| Table             | Op       | Msg_type | Msg_text                                                          |
+-------------------+----------+----------+-------------------------------------------------------------------+
| ceilometer.sample | optimize | note     | Table does not support optimize, doing recreate + analyze instead |
| ceilometer.sample | optimize | status   | OK                                                                |
+-------------------+----------+----------+-------------------------------------------------------------------+
2 rows in set (9 hours 45 min 30.02 sec)

• Ceilometer is configured to keep the last 14 days of samples:

[root@director ceilometer]# grep time_to_live /etc/ceilometer/ceilometer.conf 
metering_time_to_live=1209600
event_time_to_live=1209600