mongodb/docs — pull request #1556 by Boomtime (2014-01-30 23:35:46+00:00)
Title: $orderby should have warning for 32MB limit

cursor.sort() contains a warning about the 32MB limit on non-indexed sorting, this adds the same warning to $orderby - which is the underlying operator that powers sort().
The warning is largely a copy+paste with superficial name replacements.