Hi all,
after migrating a database from 11.2.0.4 to 12.1.0.2 we encountered some
performance issues.
The AWR report is showing this:
Top 10 Foreground Events by Total Wait Time:
Event Wait Total Wait Time (sec)
Wait Avg(ms) % DB time Wait Class
DB CPU 201.1K
75.5
resmgr.cpu.quantum 930,919 33.7K
36.22 12.7 Scheduler
I think to explain DB CPU would not be easy, but we have found by
investigating other java program on the oracle server (Redhat ) that the
ulimit was set to a lower value (1024). I'm not sure if this has to do with
DB CPU time.
Furthermore I checked the parameter resource_manager_plan and found
following:
in the new instance (12.1.2.1 RAC) the parameter is set to
MIXED_WORKLOAD_PLAN. Here we have performance problems
in the old instance (11.2.0.4 RAC) the parameter is set to null.
(Everything work as expected)
Maybe this could explain the 12.7% DB time for resmgr.cpu.quantum
Has anyone encountered problem using this parameter set to
MIXED_WORKLOAD_PLAN?
Best regards
Ahmed
