How to get datastore name for host datastore performance metrics

[sanderdescamps]

Hi,

When I query the datastore.read.average or datastore.read.average, I get an EntityMetric where the Instance of the MetricSeries is some kind of uuid. For me it is unclear where the uuid maps to. I guess it maps to the datastore but I don't know how. Is there a way I can map the metrics back to the datastore name?

This is the code that I'm using. Note that this doesn't work on the vcsim. Only on a real vcenter. The vcsim doesn't return the same metrics like a real vcenter does.

metrics := []string{"datastore.read.average", "datastore.write.average"}
hostID := "host-14"
metricInstance := "*"

perfManager := performance.NewManager(client.Client)

start := time.Now().Add(-2 * time.Minute)
end := time.Now()
pq := types.PerfQuerySpec{
	MaxSample:  5,
	MetricId:   []types.PerfMetricId{{Instance: metricInstance}},
	IntervalId: int32(20),
	StartTime:  &start,
	EndTime:    &end,
}

refs := []types.ManagedObjectReference{{Type: "HostSystem", Value: hostID}}

sample, err := perfManager.SampleByName(ctx, pq, metrics, refs)
if err != nil {
	Exit(err)
}

metricSeries, err := perfManager.ToMetricSeries(ctx, sample)
if err != nil {
	Exit(err)
}

fmt.Printf("%s,%s,%s,%s,%s,%s\n", "Host", "Time", "MetricName", "Instance", "Unit", "Value")
for _, m := range metricSeries {
	for id, sample := range m.SampleInfo {
		for _, e := range m.Value {
			value := func() string {
				if e.Value != nil {
					if len(m.SampleInfo) == len(e.Value) {
						return strconv.Itoa(int(e.Value[id]))
					} else {
						return fmt.Sprint(strings.Fields(strings.Trim(fmt.Sprint(e.Value), "[]")), "|")
					}
				}
				return "?"
			}()
			fmt.Printf("%s,%s,%s,%s,%s,%s\n", m.Entity.Value, sample.Timestamp.String(), e.Name, e.Instance, e.Unit, value)
		}
	}
}

[github-actions[bot]]

Howdy 🖐   sanderdescamps ! Thank you for your interest in this project. We value your feedback and will respond soon.

If you want to contribute to this project, please make yourself familiar with the CONTRIBUTION guidelines.

[sanderdescamps]

I've found how to link the metrics to the datastore. The uuid is the uuid of the volume defined in the host.