Viewing Heatmaps for Services and Roles
Heat maps let you compare the status or performance of the different hosts and role instances in your cluster.
From the Health Tests panel for a Service or Role instance, you can access heat maps that show related metrics for all the nodes in your cluster. These are accessed by clicking the small heatmap icon () to the right of some of the tests in the Health Tests panel for the Service or Role you are viewing.
The heatmap display shows the nodes in your cluster, one cell per node.
If you were viewing the status for a specific role, the node where that role resides is
outlined in black.
The legend at the right shows the meaning of the colors — in the example above it represents the health of a given node.
The links in the drop-down menu let you view other related metrics.
Moving the cursor over a cell in the grid (as shown above) displays the name of the node, the role, the rack assignment, and other information specific to the type of metric the map is displaying.
A second example shows metrics for a RegionServer. In this case, the
color of each cell represents a range of values (duration in milliseconds).
Moving the cursor over a cell displays the exact value for that cell, in addition to the node name and so on.