Metric Collection
Metrics are collected from each node in the cluster so that administrators can use the
data to monitor the cluster. In general, the collectd
service collects metrics
every 10 seconds. The exception is volume metrics which are collected every 10
minutes.
When collectd
writes metrics to streams, tags are assigned to each metric so
that administrators can filter metric data to create dashboards that are specific to their
needs.
By default, each metric contains the following tags:
fqdn
: Displays values for a specified node.clusterid
: Displays values for a specific cluster.clustername
: As of EEP 3.0, displays values for a specific cluster.
Streams store metrics in OpenTSDB with the following schema:
<metrictype.name> <fqdn:fqdnvalue> <clusterid:clusteridvalue> <clustername:clusternamevalue>[<AdditionalTagA:AdditionalTagAvalue> <AdditionalTagB:AdditionalTagBvalue>...] <metricvalue> <timestamp>
NOTE A negative value shown in the metrics indicates that the maximum value configured for that metric is exceeded. The maximum value for GUT metrics is int32 (2^31-1).
For more information on using tags and dashboards, see Metric Visualization.