The Key view
The Key view shows the key for graphs in the Line plot and Report displays. If the Key view is closed, click to open it.
GCMV allocates colors automatically to the lines on the graph. To override the color selection, click the colored box next to the name of the appropriate data range. Choose a different color and click OK. The change is applied to all graphs across all data sets. For example, if you choose red for heap size, the line for heap size is red on all graphs. The change is automatically saved, so the new color is used when you restart GCMV or the hosting product.