After I saw your message @stephenwaite, I logged into the server to check the log file and found the error below. I ran the same command you show. Below are the results.
[26-Jul-2017 16:56:30 America/Bogota] SQL Error with statement:insert failed: INSERT INTO openemr_postcalendar_events ( pc_catid, pc_multiple, pc_aid, pc_pid, pc_title, pc_time, pc_hometext, pc_informant, pc_eventDate, pc_endDate, pc_duration, pc_recurrtype, pc_recurrspec, pc_startTime, pc_endTime, pc_alldayevent, pc_apptstatus, pc_prefcatid, pc_location, pc_eventstatus, pc_sharing, pc_facility,pc_billing_location,pc_room ) VALUES (?,?,?,?,?,NOW(),?,?,?,?,?,?,?,?,?,?,?,?,?,1,1,?,?,?)--Unknown column 'Array' in 'field list'==>C:\emr_wamp\www\openemr\library\encounter_events.inc.php at 339:sqlInsert />
[26-Jul-2017 17:08:51 America/Bogota] PHP Fatal error: Maximum execution time of 600 seconds exceeded in C:\emr_wamp\www\openemr\interface\main\calendar\modules\PostCalendar\pnuserapi.php on line 1428
mysql> show status like '%onn%';
+-----------------------------------------------+---------------------+
| Variable_name | Value |
+-----------------------------------------------+---------------------+
| Aborted_connects | 0 |
| Connection_errors_accept | 0 |
| Connection_errors_internal | 0 |
| Connection_errors_max_connections | 0 |
| Connection_errors_peer_address | 0 |
| Connection_errors_select | 0 |
| Connection_errors_tcpwrap | 0 |
| Connections | 2903 |
| Locked_connects | 0 |
| Max_used_connections | 173 |
| Max_used_connections_time | 2017-07-27 12:10:03 |
| Performance_schema_session_connect_attrs_lost | 0 |
| Ssl_client_connects | 0 |
| Ssl_connect_renegotiates | 0 |
| Ssl_finished_connects | 0 |
| Threads_connected | 172 |
+-----------------------------------------------+---------------------+
16 rows in set (0.00 sec)
It is a good thing that the server is not hung up trying to run a job it can’t.
CPU usage rarely goes over 40%. Memory usage is at 48%. I can live with that since there is 16GB of RAM.