Thanks for exploring those views you mentioned previously, Kyle 😊.
But they're not empty data for those views marking ALERT by you. Maybe
really breached some limit (it doesn't seem like to exceed how much lines).
Best Regards
Quanwen Zhao
在 2021年12月3日星期五,kyle Hailey <kylelf@xxxxxxxxx> 写道:
some limit has been breached.
Yeah, I recall empty dba_hist_waitclassmet_history being confusing.
I believe dba_hist_waitclassmet_history is just for alerting entries when
It's been a long time since I've looked at this stuff.wrote:
Statistics
DBA_HIST_SYSMETRIC_SUMMARY – max, min, avg standard deviation
DBA_HIST_SYSSTAT (cumulative)
DBA_HIST_SYSMETRIC_HISTORY (alerts)
Waits
WAITCLASSMETRIC_HISTORY (alerts)
DBA_HIST_SYSTEM_EVENT (cumulative)
File IO
DBA_HIST_FILEMETRIC_HISTORY (alerts)
DBA_HIST_FILESTATXS (cumulative)
On Sun, Nov 28, 2021 at 12:49 AM Quanwen Zhao <quanwenzhao@xxxxxxxxx>
"v$waitclassmetric_history", and "dba_hist_waitclassmet_history". Here're
Hello Listeners 😊,
Recently I've found three important views about "v$waitclassmetric",
https://docs.oracle.com/en/database/oracle/oracle-database/19/refrn/V-WAITCLASSMETRIC.html
https://docs.oracle.com/en/database/oracle/oracle-database/19/refrn/V-WAITCLASSMETRIC_HISTORY.html#GUID-854BB495-19FC-4EB4-A81C-4D0EEA13B83C
https://docs.oracle.com/en/database/oracle/oracle-database/19/refrn/DBA_HIST_WAITCLASSMET_HISTORY.html#GUID-A931DFBF-4023-41F0-A333-E56741DE589D
recent 60-second interval. A history of the last one hour will be kept in
Quoted the brief introduction for themselves:
9.131 V$WAITCLASSMETRIC
V$WAITCLASSMETRIC displays metric values of wait classes for the most
all intervals in the last one hour.
9.132 V$WAITCLASSMETRIC_HISTORY
V$WAITCLASSMETRIC_HISTORY displays metric values of wait classes for
for V$WAITCLASSMETRIC.
The columns for V$WAITCLASSMETRIC_HISTORY are the same as those
class metric data kept by the Workload Repository.
5.84 DBA_HIST_WAITCLASSMET_HISTORY
DBA_HIST_WAITCLASSMET_HISTORY displays the history of the wait event
oracle 21.3 (test db) and found all the same situation from 19.3 and
But why dba_hist_waitclassmet_history has 0 line? Here's my query from
wait class metric to view dba_hist_waitclassmet_history or is it a bug?
16:43:23 SYS@ORACDB> select count(*) from v$waitclassmetric;
COUNT(*)
----------
13
16:43:29 SYS@ORACDB> select count(*) from v$waitclassmetric_history;
COUNT(*)
----------
793
16:43:33 SYS@ORACDB> select count(*) from dba_hist_waitclassmet_history;
COUNT(*)
----------
0
Has anybody else encountered it? Oracle hasn't saved the historical
Best Regards
Quanwen Zhao