1. A computer-implemented method for displaying performance data for a computing environment, the method comprising: determining values for a performance metric for entities that comprise the computing environment; and displaying the computing environment as a tree comprising nodes representing the entities and edges representing parent-child relationships between the entities; wherein while displaying each leaf node in the tree, the method comprises: comparing the values of the performance metric against one or more state-specific threshold values to determine a performance state for the leaf node; and displaying the leaf node as a first shape comprising an indicator for the performance state for the leaf node; wherein while displaying each parent node in the tree, the method comprises: determining a performance state of the parent node based on a worst performance state of any child node under the parent node; displaying the parent node as second shape comprising an indicator of the performance state of the parent node; and wherein while displaying a set of child nodes for each parent node, the method comprises: determining a performance state for each child node in the set based on a value of the performance metric for an entity associated with the child node, wherein a set of possible performance states vary in severity; wherein if a child node in the set has descendants in the tree, the performance state for the child node includes count of performance states for the descendants of the child node, and determining a sorted order for the set of child nodes based on counts of descendants of the child nodes having a most-severe performance state; and displaying the set of child nodes in the sorted order.