Robert Haas <robertmhaas@xxxxxxxxx> writes: > ...but that begs the question of why DROP INDEX needs an > AccessExclusiveLock. It probably needs such a lock *on the index* but > I don't see why we'd need it on the table. Some other session might be in process of planning a query on the table. It would be sad if the index it had chosen turned out to have vanished meanwhile. You could perhaps confine DROP INDEX's ex-lock to the index, but only at the price of making the planner take out a lock on every index it considers even transiently. Which isn't going to be a net improvement. (While we're on the subject, I have strong suspicions that most of what Simon did this cycle on ALTER TABLE lock strength reduction is hopelessly broken and will have to be reverted. It's on my to-do list to try to break that patch during beta, and I expect to succeed.) regards, tom lane -- Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance
