Inconsistency between v$sysstat and v$sys_time_mode
434623Jun 6 2012 — edited Jun 6 2012Hi,
I hit a strange problem recently. I am tuning a heavy batch workload on db. So I restart instance and run batch. I am monitoring v$sysstat and v$sys_time_model during batch (among others). And there is a huge difference between statistics 'parse time elapsed' between them.
I created following sql to demonstrate this:
SELECT s.name, trunc((s.value / 100 / 60 /60),2) hours FROM v$sysstat s where s.name in ('parse time elapsed', 'DB time');
select stat_name, trunc(value / 1000000 / 60 /60,2) hours from v$sys_time_model where stat_name in ('parse time elapsed','DB time') ;
Difference if really huge, after 12hours batch first query returns about 3% of db time spent on parsing, but the second one returns about 40%. In number it is 5hours vs 20minutes.
I am quite confused, where is the true? And why there is such big difference.
Thank you for help.
DB version 10.2.0.4.0 - 64bit Enterprise Edition, Linux