private void restoreGroupedVertices() {
		FGController controller = functionGraphView.getController();
		Element groupedVertexXML = functionGraph.getSavedGroupedVertexSettings();
		if (groupedVertexXML != null) {
			GroupVertexSerializer.recreateGroupedVertices(controller, groupedVertexXML);
		}

		Element regroupVertexXML = functionGraph.getSavedGroupHistory();
		if (regroupVertexXML != null) {
			Collection<GroupHistoryInfo> history =
				GroupVertexSerializer.recreateGroupHistory(controller, regroupVertexXML);
			functionGraph.setGroupHistory(history);
		}
	}
A somewhat arbitrary value that is used to signal a 'big' graph, which is one that will
slow down the system during the rendering process.
Ghidra/Features/FunctionGraph/src/main/java/ghidra/app/plugin/core/functiongraph/graph/FGComponent.java