A time-series plot for a service, role, or host may actually be a composite of multiple
individual time series. Using facets, you can combine time series based their attributes.
For example, the query SELECT
jvm_heap_used_mb where clusterId = 1 returns time-series data for the JVM heap
used. Each time series has hostname, role type, metric, and entity name attributes. By default
each attribute is displayed all on a single chart.
To change the organization of the chart data, click
one of the facets in the facet section in the upper part of the screen.
The number in parentheses indicates how many charts will be displayed for
that facet. As shown in the image below if the serviceName facet is
selected for the JVM heap query, the time series is grouped into six
charts, one chart each for each service name. The charts for service types
with multiple roles contain multiple lines (for example, HBase, HDFS)
while services that have only one role (for example, ZooKeeper) contain
just a single line. When a chart contains multiple lines, each entity is
identified by a different color line.