"brianb" <brianb-pggeneral(at)evoserve(dot)com> writes:
> I have a Postgres application that must run 24x7. If postgres needs to be
> vacuumed periodically, must I take the application offline completely, or
> is it enough to disallow write (INSERT/UPDATE) access while allowing read
> access?
You're wasting your time to think of allowing or disallowing access;
VACUUM is quite capable of locking out other accesses without help ;-)
The short answer is that a table being vacuumed is locked against any
other access, read or write; but only that one table. You might as
well leave the rest of the database open for use.
regards, tom lane