--- a/contrib/revsetbenchmarks.py	Thu Jun 11 10:55:02 2015 -0700
+++ b/contrib/revsetbenchmarks.py	Fri Jun 12 16:42:07 2015 -0400
@@ -95,7 +95,10 @@
 def idxwidth(nbidx):
     """return the max width of number used for index
 
-    Yes, this is basically a log10."""
+    This is similar to log10(nbidx), but we use custom code here
+    because we start with zero and we'd rather not deal with all the
+    extra rounding business that log10 would imply.
+    """
     nbidx -= 1 # starts at 0
     idxwidth = 0
     while nbidx: