Tom Lane wrote:

Bryce Nesbitt <bryce2@obviously.com> writes:

1) Why the AccessExclusiveLock on create table?


It has to install a trigger on the referenced table.  There has been
some discussion that maybe CREATE TRIGGER could take just ExclusiveLock
and not AccessExclusiveLock, but it hasn't been done yet; and I'm not
sure how much that would help you anyway.  It would only help if the
referenced table (contexts) is essentially read-only to the rest of
your workload, else it'll block anyhow.

Thanks for the great info.

In our case all the long running access is read-only. We have a poorly designed table that several postgres consultants have burned out on trying to fix.

Most notably there are also zillions of short read-only references that presently block while the create table attempts to gain the AccessExclusiveLock.

-Bryce