Identity error

Discussion created by marshallsf on Nov 13, 2013
Latest reply on Nov 15, 2013 by marshallsf
I have a feature class containing ~300k polygon features. The features include identical overlapping polygons produced from Unioning a single feature class, as described here: The original dataset consisted of features stacked 100 or more in some areas, translating to 100 or more identical overlapping polygons in the new, Unioned feature class. My input and output data both reside in a file geodatabase.

Now I want to create a dictionary of overlaps. As a first step, I want to run Identity on the feature class containing the overlapping polygons to be able to compare overlapping OIDs, but after about 30 minutes the tool fails with a 999999 error and the output table is cleaned up before I can examine it. It may be that the complexity and/or depth of overlaps is causing a problem, but the tool results don't provide enough information to know.

I'm running the tool inside ArcGIS Desktop with 64-bit background processing enabled and monitoring the tool's memory usage, which is a little above 2GB at its peak, but the tool doesn't fail when the usage is at its highest. Also, the tool output doesn't indicate an out-of-memory error.

The input features are not complex in terms of their number of vertices, so Dice doesn't seem to be applicable here. The output does say "Processing Tiles...", however, which I assume means the dataset is large enough to tile:

What are the limitations of Identity? Is there a recognized maximum number of features or levels of overlap that would cause it to fail? If so, is there a known workaround?