Hello, While understanding the effect of maintenance_work_mem on time taken by CREATE INDEX, I observed that for the values of maintenance_work_mem less than the value for which an internal sort is performed, the time taken by CREATE INDEX increases as maintenance_work_increases. My guess is that for all those values an external sort is chosen at some point and larger the value of maintenance_work_mem, later the switch to external sort would be made causing CREATE INDEX to take longer. That is a smaller value of maintenance_work_mem would be preferred for when external sort is performed anyway. Does that make sense? -- Amit Langote -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general