Using Enterprise Edition 12.1.0.2 non-CDB with database created by DBCA. All defaults. I noticied everything in EM Express works fine except the Activity tab is blank. I ran a SwingBench 400 user workload for 4 hours, and the Activity tab never populated, and on the Workload tab the two charts are working fine but the Top SQL is not populated. I suspected ASH data is not being collected by Oracle. As you can see below, the views V$ACTIVE_SESSION_HISTORY and DBA_HIST_ACTIVE_SESS_HISTORY are both empty. Why would this happen, and how to fix it?
$ sqlplus / as sysdba
SQL*Plus: Release 12.1.0.2.0 Production on Thu Jun 16 13:28:34 2016
Copyright (c) 1982, 2014, Oracle. All rights reserved.
Connected to:
Oracle Database 12c Enterprise Edition Release 12.1.0.2.0 - 64bit Production
With the Partitioning, Automatic Storage Management, OLAP, Advanced Analytics
and Real Application Testing options
SQL> show parameter control_man
NAME TYPE VALUE
------------------------------------ ----------- ------------------------------
control_management_pack_access string DIAGNOSTIC+TUNING
SQL> show parameter statistic
NAME TYPE VALUE
------------------------------------ ----------- ------------------------------
optimizer_use_pending_statistics boolean FALSE
statistics_level string TYPICAL
timed_os_statistics integer 0
timed_statistics boolean TRUE
SQL> show parameter resource_m
NAME TYPE VALUE
------------------------------------ ----------- ------------------------------
resource_manager_cpu_allocation integer 80
resource_manager_plan string DEFAULT_PLAN
SQL> select * from dba_hist_active_sess_history;
no rows selected
SQL> select * from v$active_session_history;
no rows selected