Search notes:
Oracle: Init parameter TIMED_STATISTICS
Setting timed_statistics to true enabled the collection of timed statistics by the SQL Trace facility (such as column CPU and ELAPSED in TKPROF).
For some statistics found in
v$sesstat and
v$sysstat to be taken, the value of
timed_statistics must be set to
true. These statistics include (
21c?):
- change write time
- CPU used by this session
- CPU used when call started
- process last non-idle time
- redo log space wait time
- redo synch time
- redo write broadcast ack time
- redo write time
- session connect time
The
value of
timed_statistics depends on the value of
statistics_level, it must be
true if
statistics_level is not
basic.
column name format a16
column value format a7
select p.name, p.value
from v$parameter p
where p.name in ( 'statistics_level', 'timed_statistics' );
--
-- NAME VALUE
-- ---------------- -------
-- timed_statistics TRUE
-- statistics_level TYPICAL
alter session set statistics_level = basic;
select p.name, p.value
from v$parameter p
where p.name in ( 'statistics_level', 'timed_statistics' );
--
-- NAME VALUE
-- ---------------- -------
-- timed_statistics TRUE
-- statistics_level BASIC
alter session set timed_statistics = false;
select p.name, p.value
from v$parameter p
where p.name in ( 'statistics_level', 'timed_statistics' );
--
-- NAME VALUE
-- ---------------- -------
-- timed_statistics FALSE
-- statistics_level BASIC
alter session set statistics_level = typical;
> ORA-02097: parameter cannot be modified because specified value is invalid
> ORA-00044: timed_statistics must be TRUE when statistics_level is not BASIC
See also
timed_os_statistics