Hello all,
there is a big discrepancy between DB Time and (waits + DB CPU) in the AWR.
Time model statistics:

Foreground wait class:

Background waits:

The CPU of the machine was 100% utilized. So I think that it can be the root cause of the discrepancy. It's AIX machine, 12.1.0.2.0, NO RAC, enterprise.
Any ideas of the root cause of such a big difference, please?
Thanks,
Jakub.