A query of the form SELECT * FROM (SELECT * FROM table1 WHERE...) JOIN (SELECT * FROM table2 WHERE...) USING (table2_primary_key_columns) LIMIT 1000 causes nodes to run out of memory. (We have more schema details and the exact query in a non-public bug report) It looks like something memory is not being accounted for correctly. (blaming this on the use of a join on two subqueries is just a guess on my part)