6.0.1

Table 1‑2. Data Counter Attributes (Continued)
Attribute Description
Statistics Type Measurement used during the statistics interval. Related to the unit of measurement.
n
Rate – Value over the current statistics interval
n
Delta – Change from previous statistics interval.
n
Absolute – Absolute value (independent of the statistics interval).
Rollup Type Calculation method used during the statistics interval to roll up data. Determines the type of
statistical values that are returned for the counter.
n
Average – Data collected during the interval is aggregated and averaged.
n
Minimum – The minimum value is rolled up.
n
Maximum – The maximum value is rolled up.
The Minimum and Maximum values are collected and displayed only in statistics level 4.
Minimum and maximum rollup types are used to capture peaks in data during the interval.
For real-time data, the value is the current minimum or current maximum. For historical data,
the value is the average minimum or average maximum.
For example, the following information for the CPU usage chart shows that the average is
collected at statistics level 1 and the minimum and maximum values are collected at statistics
level 4.
n
Counter: usage
n
Unit: Percentage (%)
n
Rollup Type: Average (Minimum/Maximum)
n
Collection Level: 1 (4)
n
Summation – Data collected is summed. The measurement displayed in the chart represents
the sum of data collected during the interval.
n
Latest – Data collected during the interval is a set value. The value displayed in the
performance charts represents the current value.
Collection level Number of data counters used to collect statistics. Collection levels range from 1 to 4, with 4
having the most counters.
NOTE Be careful when you set a higher collection level, as the process requires significant increase
of resource usage. For more information, see “Data Collection Levels,” on page 13.
Metric Groups in vSphere
The performance data collection subsystem for vSphere collects performance data on a variety of inventory
items and their devices. Data counters define individual performance metrics. Performance metrics are
organized into logical groups based on the object or object device. Statistics for one or more metrics can be
displayed in a chart.
Table 1‑3. Metric Groups
Metric group Description
Cluster
Services
Performance statistics for clusters configured by using vSphere Distributed Resource Scheduler,
vSphere High Availability, or both.
CPU CPU utilization per host, virtual machine, resource pool, or compute resource.
Datastore Statistics for datastore utilization.
Disk Disk utilization per host, virtual machine, or datastore. Disk metrics include I/O performance, such as
latency and read/write speeds, and utilization metrics for storage as a finite resource.
Memory Memory utilization per host, virtual machine, resource pool, or compute resource. The value obtained
is one of the following:
n
For virtual machines, memory refers to the guest physical memory. Guest physical memory is the
amount of physical memory presented as a virtual-hardware component to the virtual machine, at
creation time, and made available when the virtual machine is running.
n
For hosts, memory refers to the machine memory. Machine memory is the RAM that is installed on
the hardware that comprises the host.
Chapter 1 Monitoring Inventory Objects with Performance Charts
VMware, Inc. 11