diff --git a/compass/ocean/tests/global_ocean/performance_test/__init__.py b/compass/ocean/tests/global_ocean/performance_test/__init__.py
index e01e83cf1c..2845cb991f 100644
--- a/compass/ocean/tests/global_ocean/performance_test/__init__.py
+++ b/compass/ocean/tests/global_ocean/performance_test/__init__.py
@@ -1,6 +1,7 @@
 from compass.validate import compare_variables, compare_timers
 from compass.ocean.tests.global_ocean.forward import ForwardTestCase, \
     ForwardStep
+from compass.ocean.inactive_top_cells import remove_inactive_top_cells_output
 
 
 class PerformanceTest(ForwardTestCase):
@@ -61,6 +62,18 @@ def validate(self):
         compare_variables(test_case=self, variables=variables,
                           filename1='forward/output.nc')
 
+        if self.config.has_option('vertical_grid', 'inactive_top_cells'):
+            offset = self.config.getint('vertical_grid', 'inactive_top_cells')
+            if offset > 0:
+                remove_inactive_top_cells_output('forward/output.nc',
+                                                 inactive_top_cells=offset)
+                variables = [
+                    'temperature', 'salinity', 'layerThickness', 'normalVelocity']
+                compare_variables(test_case=self, variables=variables,
+                                  filename1='forward/output_crop.nc',
+                                  filename2='forward/output_comp.nc',
+                                  quiet=False, check_outputs=False)
+
         if self.mesh.with_ice_shelf_cavities:
             variables = [
                 'ssh', 'landIcePressure', 'landIceDraft', 'landIceFraction',