Question: How can I tell of I have an
overloaded CPU? I know that the 100% utilization is normal,
but I heard that the "resmgr:cpu quantum" event indicates that tasks
are waiting for CPU resources.
Answer:
The wait event resmgr:cpu quantum is a
normal wait event used by the Oracle Resource Manager to
control CPU distribution. The resmgr:cpu quantum
only occurs when the resource manager is enabled and the
resource manage is "throttling" CPU consumption.
You
can also detect an overloaded CPU when you see the
"resmgr:cpu quantum" event in a top-5 timed event on a AWR
or STATSPACK report.
The "resmgr:cpu quantum" only applies when the Oracle
resource manager is deployed, and there are other ways to
detect an overloaded CPU:
1 - UNIX/Linux - vmstat
when the runqueue column (r) exceed the cpu_count for the
database
2 Windows: When the
processor queue length is greater than zero. See
detecting_windows_cpu_processor_bottlenecks.