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Table Of Contents
Table 11. CPU Metric Group (Continued)
Metric Description
Summary|Number of running VMs This metric shows the number of running VMs at a given
point in time. The data is sampled every ve minutes.
A large number of running VMs might be a reason for CPU
or memory spikes because more resources are used in the
host. The number of running VMs gives you a good
indicator of how many requests the ESXi host must juggle.
Powered o VMs are not included because they do not
impact ESXi performance. A change in the number of
running VMs can contribute to performance problems. A
high number of running VMs in a host also means a higher
concentration risk, because all the VMs will fail if the ESXi
crashes.
Use this metric to look for a correlation between spikes in
the running VMs and spikes in other metrics such as CPU
contention, or memory contention.
Summary|Number of vMotions This metric shows the number of times a live migration
(vMotion) with no VM downtime or service disruption
took place in a host in the last (x) minutes.
The number of vMotions is a good indicator of stability. In
a healthy environment, this number is stable and relatively
low.
When using this metric, look for a correlation between
vMotions and spikes in other metrics such as CPU
contention and memory contention. Although the vMotion
should not create any spikes, it is highly likely that some
spikes in memory usage contention, and CPU demand and
contention are experienced.
Chapter 1 Monitoring Objects in Your Managed Environment by Using vRealize Operations Manager
VMware, Inc. 47