Robert Haas <robertmh...@gmail.com> writes: > I have been thinking for a while now that it would be sensible to make > vacuum use a different lock type, much as we do for relation > extension.
Hmm. I had just been toying with the idea of introducing a new user-visible locking level to allow separation of anti-vacuum locks from anti-schema-alteration locks. But I think you're probably right that it could be done as a specialized LockTag. That would make it not easily user-accessible, but it's hard to think of reasons for users to lock out vacuum anyway, unless they want to lock out everything via AccessExclusiveLock. > ... In particular, it's currently not > possible to lock a table against SELECT without also locking it > against VACUUM Well, it still wouldn't be, since AccessExclusiveLock certainly had better lock out vacuum. As said above, I think the important thing is to distinguish vacuum from schema changes. > But that's not something I want to do in 9.1, Definitely. regards, tom lane -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers